DiO and DiD are lipophilic cell labelling dyes used in the staining of cells in vivo and in vitro. The aim of the present study was to quantify the asymmetrical distribution of dyes in co‑cultured cells and to measure the intercellular transfer of DiO and DiD. DiO and DiD were applied separately to stain two identical populations of SW‑1353 human chondrosarcoma cells that were subsequently co‑cultured (homotypic co‑culture). The intercellular migration of dyes in the co‑cultured cells was measured by flow cytometry and recorded under a fluorescent microscope. DiD and DiO caused no effect on the proliferation of cells, the degradation rate of the two dyes was comparable and crossover effects between dyes were negligible. The results of the present study suggested that asymmetrical intercellular migration of DiD and DiO was responsible for the asymmetrical distribution of these dyes in co‑cultured cells. To take advantage of the lipophilic dyes migration in the double-stained co-cultured cells we suggest to apply mixed-dyes controls prior to the flow cytometric analysis. These controls are performed by staining cells with a 1:1 mix of the two dyes and would enable the estimation of the intensity of intercellular contact in co‑culture systems. A 1:1 premix of DiO and DiD was applied to estimate cellular effect on intercellular exchange of lipid dyes in co‑cultures incubated with cycloheximide and cytochalasin B. The cellular effect contributed 6‑7% of intercellular migration of the lipophilic dyes, DiO and DiD. The majority of the observed intercellular transfer of these dyes was due to non‑cellular, passive transfer.

Increased cell apoptosis in chondrocytes is a feature of degenerative cartilage. Astragaloside IV (AST) has been proven to possess an antiarthritic effect by preventing interleukin (IL)‑1β‑induced cartilage damage. However, the role of AST on chondrocyte apoptosis and its underlying mechanism remains unknown. In the present study, degenerative chondrocytes isolated from patients with osteoarthritis (OA) were subjected to AST and IL‑1β treatment. Results indicated that AST protected against chondrocyte apoptosis induced by IL‑1β. Western blotting indicated that AST increased the protein expression of LC3‑II/I and decreased P62/SQSTM1 expression, which suggested that AST upregulated autophagy activity in chondrocytes. Fluorescent protein GFP‑LC3 analysis and transmission electron microscopy observation confirmed that autophagy was promoted by AST. In contrast, after autophagy inhibited by 3‑methyladenine, chondrocyte apoptosis was further increased under IL‑1β treatment. Ultimately, rapamycin was used as a positive control, whose results confirmed that rapamycin‑mediated autophagy also decreased chondrocyte apoptosis induced by IL‑1β. In conclusion, these results suggested that AST‑mediated autophagy serves an anti‑apoptotic role in chondrocytes, which may aid the development of novel therapeutic approaches for OA treatment.

Indian hedgehog protein (Ihh) is evolutionarily conserved and serves important roles in controlling the differentiation of progenitor cells into osteoblasts. Ihh null mutant mice exhibit a failure of osteoblast development in endochondral bone. Although studies have demonstrated that Ihh signaling is a potent local factor that regulates osteoblast differentiation, the specific transcription factors that determine osteoblast differentiation remain unclear. Further studies are required to determine the precise mechanism through which Ihh regulates osteoblast differentiation. In the present study, Ihh was knocked down in osteoblast MC3T3‑E1 cells using short hairpin RNA, to investigate the function of Ihh in osteoblast proliferation and differentiation and to examine the potential mechanism through which Ihh induces osteoblast apoptosis and cell cycle arrest. It was observed that the knockdown of Ihh induced a marked inhibition of cell growth and increased the apoptosis rate compared with the negative control osteoblasts. Downregulation of Ihh resulted in a cell cycle arrest at the G1 to S phase boundary in osteoblasts. In addition, the knockdown of Ihh decreased the alkaline phosphatase activity and mineral deposition of osteoblasts. The inhibitory roles of Ihh downregulation in osteoblast growth and differentiation may be associated with the transforming growth factor‑β/mothers against decapentaplegic homolog and tumor necrosis factor receptor superfamily member 11B/tumor necrosis factor ligand superfamily member 11 signaling pathways. Manipulating either Ihh expression or its signaling components may be of benefit for the treatment of skeletal diseases.

The aim of the present study was to determine the effects of early anticoagulation treatment on severe burns complicated by inhalation injury in a rabbit model. Under anesthetization, an electrical burns instrument (100˚C) was used to scald the backs of rabbits for 15 sec, which established a 30% III severe burns model. Treatment of the rabbits with early anticoagulation effectively improved the severe burns complicated by inhalation injury‑induced lung injury, reduced PaO2, PaCO2 and SPO2 levels, suppressed the expression of tumor necrosis factor‑α, interleukin (IL)‑1β and IL‑6, and increased the activity of IL‑10. In addition, it was found that early anticoagulation treatment effectively suppressed the activities of caspase‑3 and caspase‑9, upregulated the protein expression of vascular endothelial growth factor (VEGF) and decreased the protein expression of protease‑activated receptor 1 (PAR1) in the severe burns model. It was concluded that early anticoagulation treatment affected the severe burns complicated by inhalation injury in a rabbit model through the upregulation of VEGF and downregulation of PAR1 signaling pathways. Thus, early anticoagulation is a potential therapeutic option for severe burns complicated by inhalation injury.

The present study aimed to compare the expression levels of excitatory amino acid transporters (EAATs) and growth status of piglets weaned at 10‑20 days after birth with suckling piglets. A total of 40 hybrid piglets (Landrace x Large White x Duroc) born to 40 different sows, with similar body weight were selected for the present study. They were randomly divided into two groups (n=20 per group): Control group (suckling piglets) and experimental group (weaned piglets, reared in isolation). The experiment lasted for 10 days. At the end of the experiment, 12 piglets were randomly selected from each group and the jejunum and the ileum were collected in order to determine excitatory amino acid carrier 1 (EAAC1) expression levels and free amino acid content. The present study determined that early weaning significantly reduced EAAC1 gene and protein (57 and 73 kDa) expression levels and glutamate transporter associate protein 3‑18 (GTRAP3‑18; 50 kDa) in the jejunum and the ileum compared with the suckling group (P<0.05). Weaning led to an increased content of free glutamic acid (Glu) and total amino acids in the jejunum; however, content of free Glu and total amino acids in the ileum was significantly reduced (P<0.05). Early weaning reduced the expression of EAAC1 and GTRAP3‑18, which was possibly due to the amino acid absorption and transport disorder in the small intestine due to the Glu deficiency.

The ability of mesenchymal stem cells (MSCs) to differentiate into osteogenic lineages requires management for their future use in treating bone destruction and osteoporosis. Hepcidin is closely associated with bone metabolism, however, it remains to be elucidated whether hepcidin affects osteogenic differentiation in MSCs. The present study demonstrated that hepcidin enhanced osteoblastic differentiation and mineralization, which was manifested by an upregulation in the differentiation markers alkaline phosphatase and osteogenic genes. Furthermore, the expression levels of bone morphogenetic proteins and small mothers against decapentaplegic homologs were concomitantly increased following hepcidin treatment. In addition, the p38 mitogen-activated protein kinase may be an upstream kinase for osteoblastic differentiation. Thus, hepcidin may be important in the osteogenic differentiation of MSCs and may be considered as a target in the development of therapies for pathological bone loss.

The 448 kHz capacitive‑resistive electric transfer (CRET) is an electrothermal therapy currently applied in anticellulite and antiobesity treatments. The aim of the present study was to determine whether exposure to the CRET electric signal at subthermal doses affected early adipogenic processes in adipose‑derived stem cells (ADSC) from human donors. ADSC were incubated for 2 or 9 days in the presence of adipogenic medium, and exposed or sham‑exposed to 5 min pulses of 448 kHz electric signal at 50 µA/mm2 during the last 48 h of the incubation. Colorimetric, immunofluorescence, western blotting and reverse transcription‑quantitative polymerase chain reaction assays were performed to assess adipogenic differentiation of the ADSC. Electric stimulation significantly decreased cytoplasmic lipid content, after both 2 and 9 days of differentiation. The antiadipogenic response in the 9 day samples was accompanied by activation of mitogen‑activated protein kinase kinase 1/2, decreased expression and partial inactivation of peroxisome proliferator‑activated receptor (PPAR) γ, which was translocated from the nucleus to the cytoplasm, together with a significant decrease in the expression levels of the PPARG1 gene, perilipin, angiopoietin‑like protein 4 and fatty acid synthase. These results demonstrated that subthermal stimulation with CRET interferes with the early adipogenic differentiation in ADSC, indicating that the electric stimulus itself can modulate processes controlling the synthesis and mobilization of fat, even in the absence of the concomitant thermal and mechanical components of the thermoelectric therapy CRET.

As a heat shock protein 90 inhibitor, 17-allylamino-17‑demethoxygeldanamycin (17-AAG) has been studied in numerous types of cancer, however the effects of 17-AAG on apoptosis and the cell cycle of H446 cells remain unclear. In the current study, the MTT method was used to evaluate the inhibitory effects of different durations and doses of 17‑AAG treatment on the proliferation of H446 cells. The cells were stained with Annexin-fluorescein isothiocyanate/propidium iodide and measured by flow cytometry, and the gene and protein expression levels of signal transducer and activator of transcription 3 (STAT3), survivin, cyclin D1, cyt‑C, caspase 9 and caspase 3 were determined by reverse transcription‑quantitative polymerase chain reaction and western blot analysis. The results indicated that with treatment with 1.25‑20 mg/l 17‑AAG for 24 and 48 h, significant inhibition of H446 cell proliferation was observed in a time‑ and dose‑dependent manner. With treatment of 3.125, 6.25 and 12.5 mg/l 17‑AAG for 48 h, significant apoptosis and cell cycle arrest was observed. The results indicated that the gene and protein expression levels of STAT3, survivin and cyclin D1 were downregulated, and cyt‑C, caspase 9 and caspase 3 were upregulated by 17‑AAG in a dose-dependent manner when the cells were treated with 3.125 and 6.25 mg/l 17-AAG for 48 h. The results indicated that 17‑AAG is able to inhibit the cell proliferation, induce apoptosis and G2/M arrest and downregulate the gene and protein expression levels of STAT3, survivin and cyclin D1, and upregulate gene and protein expression of cyt‑C, caspase 9, caspase 3.

Fatty acid synthase (FASN), a lipogenic multi-enzyme complex, is reported to be overexpressed in various types of of tumor tissues and serves an important role in tumor development and progression. However, the expression of FASN and its possible role in gastric cancer (GC) remains to be defined. In the present study, FASN expression in a group sample of 167 GC tissues was detected by immunohistochemistry and its correlation with clinicopathological features was analyzed. By clinical analysis, it was identified that FASN overexpression was positively correlated with the overall survival [P=0.008; hazard ratio (HR), 4.412; 95% confidence interval (CI), 1.463‑13.305] and recurrence rate (P=0.014; HR, 1.705; 95% CI, 1.116‑2.606) in patients with GC. In addition, expression of the FASN protein in GC tissues was correlated with age (P=0.032), clinical stage (P<0.001), gastric wall invasion (P=0.014), lymph node metastasis (P<0.001) and distant metastasis (P<0.001), however not with gender (P>0.05). In addition, FASN was observed to be overexpressed in GC tissues at an mRNA and protein level, compared with the adjacent non-cancerous tissues (P<0.05). Taken together, it was suggested that FASN was closely associated with GC metastasis and survival, which further provided evidence that FASN may be a promising prognostic biomarker for patients with GC.

The present study aimed to investigate whether bone morphogenetic protein‑2 (BMP‑2) was involved in the repair of mandibular defects using polyether‑ether‑ketone biphasic bioceramic (PEEK‑BBC) composites in rabbits. PEEK‑BBC composites with abundant and interconnected pores were prepared by calcination and characterized by scanning electron microscope. A mandibular defect model in rabbits was established using dental grinder to produce a square hole. A total of 60 rabbits were divided into four groups: Control, sham, surgery, and PEEK. In the PEEK group, the holes were filled with the PEEK‑BBC composite stents. In the surgery group, the holes were produced but not filled with the composite stents. In the sham group, only the molar grooves were exposed and grinding was not performed. Animals without any treatment served as the control group. The success rate of model establishment was 100%. At 4, 8, and 16 weeks after the model was established, samples were collected from the molding sites. Bone repair was evaluated by H&E staining and Goldner trichrome staining. Bone structures in both control and sham groups were intact. A small number of osteocytes were observed in the surgery group. However, in the PEEK group, osteocytes were already evidently present in the composites at 4 weeks after surgery. At 8 and 16 weeks, there were large numbers of osteocytes in the pores of the composites. The mRNA and protein expression levels of BMP‑2 were determined by reverse transcription‑quantitative polymerase chain reaction and western blotting, respectively. The mRNA and protein expression levels of BMP‑2 between the control and sham groups were similar and were continuously stable. However, following defect treatment, BMP‑2 mRNA and protein expression was upregulated, which was enhanced by the PEEK‑BBC composites. In conclusion, PEEK‑BBC composites promoted the growth of osteocytes and repaired mandibular defects in rabbits, potentially via the upregulation of BMP‑2 expression.

Hypoxia, which is an important factor that mediates tumor progression and poor treatment response, is particularly associated with tumor chemoresistance. However, the molecular mechanisms underlying hypoxia-induced colorectal cancer chemoresistance remain unclear. The present study aimed to explore the mechanism underlying hypoxia‑induced chemotherapy resistance in LOVO colorectal cancer cells. LOVO cells were cultured in a hypoxic environment simulated by cobalt chloride (CoCl2), which is a chemical inducer of hypoxia‑inducible factor‑1α (HIF‑1α). HIF‑1α is a transcription factor that has an important role in tumor cell adaptation to hypoxia, and controls the expression of several genes. Various CoCl2 concentrations are often used to simulate degrees of hypoxia. In the present study, following treatment with CoCl2, an MTT assay was conducted to determine the growth and drug sensitivity of LOVO cells. Reverse transcription‑polymerase chain reaction and western blotting were used to detect the mRNA and protein expression levels of HIF‑1α and factors associated with chemotherapy resistance, including multidrug resistance protein (MRP) and multidrug resistant 1 (MDR1), which encodes the major transmembrane efflux transporter P‑glycoprotein (P‑gp). In addition, the expression levels of apoptosis‑related proteins, including B‑cell lymphoma 2 (Bcl‑2), Bcl‑2‑associated X protein (Bax) and Bcl‑2‑associated agonist of cell death (Bad) were detected by western blotting. Flow cytometry (FCM) was used to visually observe Adriamycin (ADR) accumulation and retention, thus analyzing intracellular drug transportation in cells under hypoxic and normoxic conditions. CoCl2‑simulated hypoxia was able to inhibit tumor cell proliferation, and upregulate the expression levels of HIF‑1α, MDR1/P‑gp and MRP. In addition, proapoptotic members of the Bcl‑2 protein family, Bax and Bad, were downregulated. The anti‑apoptotic member Bcl‑2 exhibited no significant change in expression, whereas the ratio of Bcl‑2/Bax was increased. Results of FCM demonstrated that the intracellular retention of ADR was significantly decreased in the hypoxia group cells. In conclusion, the present study revealed that a CoCl2-simulated hypoxic microenvironment was able to effectively induce chemoresistance and reduce apoptosis in LOVO cells.

To investigate the effects of silica on circulating fibrocytes (cFbs), the present study established a primary culture model of rat alveolar macrophages and cFbs in vitro. Macrophages were treated with free silica, and their supernatant was used to stimulate cFbs. The mRNA expression levels of collagen I, collagen III and α‑smooth muscle actin (SMA) in cFbs were analyzed by reverse transcription‑quantitative polymerase chain reaction. The intracellular and extracellular protein expression levels of collagen I, collagen III and α‑SMA were detected by ELISA and immunofluorescence staining. The results indicated that in the cell model, the free silica effectively increased the protein and mRNA expression levels of collagen‑I, collagen‑III and α‑SMA. The free silica significantly promoted the transdifferentiation of cFbs into myofibroblasts in a dose‑and time-dependent manner.

The molecular mechanisms underlying protection and pathogenesis in spinal degenerative diseases remain unclear. Tumor necrosis factor-α (TNF-α) has been demonstrated to induce apoptosis of inte rvertebral disc (IVD) cells during IVD degeneration, and 17β‑estradiol (17β‑E2) has a protective effect against IVD cell apoptosis. However, the underlying molecular mechanism by which 17β‑E2 protects nucleus pulposus (NP) cells remains to be investigated. The aim of the present study was to evaluate whether 17β‑E2 modulates apoptosis of human NP cells induced by TNF‑α. In addition, the concentration‑response effect of 17β‑E2 on human NP cells was investigated. Human NP cells were cultured in complete medium, which was replaced every three days until the culture was ~80% confluent. Cells were treated with 100 ng/ml TNF‑α for 48 h, with or without pretreatment with various concentrations of 17β‑E2, and ICI 182,780, for 30 min. Morphologic alterations characteristic of apoptosis were observed by inverted phase‑contrast microscopy and Hoechst 33258 staining; the apoptosis rate was analyzed by flow cytometry. A Cell Counting kit‑8 assay was used to assess cell proliferation. Furthermore, caspase‑3 activity was determined and proteins associated with apoptosis were analyzed by western blotting. The level of apoptosis and caspase‑3 activity in human NP cells increased, whereas proliferation and the expression of poly ADP‑ribose polymerase decreased following TNF‑α treatment. These effects of TNF‑α were abolished by pretreatment with 17β‑E2 in a concentration‑dependent manner. The results of the present study indicated that 17β‑E2 serves a critical role in the survival of degenerative human NP cells.

Hypoxia may induce apoptosis and autophagy to promote cardiomyocyte injury. The present study investigated the effect of berberine, a natural extract of Rhizoma Coptidis, on hypoxia‑induced autophagy and apoptosis in the H9c2 rat myocardial cell line. Expression levels of apoptosis and autophagy markers were upregulated in H9c2 myocytes during hypoxia and cell viability was reduced. However, berberine significantly reduced hypoxia‑induced autophagy in H9c2 myocytes, as demonstrated by the ratio of microtubule‑associated proteins 1A/1B light chain 3 I/II and the expression levels of B‑cell lymphoma 2 (Bcl‑2)/adenovirus E1B 19 kDa protein‑interacting protein 3, and promoted cell viability. In addition, expression levels of the Bcl‑2 anti‑apoptotic protein were significantly downregulated, and expression levels of pro‑apoptotic proteins Bcl‑2‑associated X protein and cleaved caspase‑3 were upregulated during hypoxia injury in cardiac myocytes. This was reversed by treatment with berberine or the autophagy inhibitor 3‑methyladenine, whereas the autophagy agonist rapamycin had the opposite effects, suggesting that berberine reduces myocyte cell death via inhibition of autophagy and apoptosis during hypoxia. In addition, Compound C, a 5' adenosine monophosphate‑activated protein kinase (AMPK) inhibitor, reduced apoptosis and autophagy in hypoxic myocytes, suggesting that the activation of the AMPK signaling pathway may be involved in this process. These findings suggested that berberine protects cells from hypoxia‑induced apoptosis via inhibition of autophagy and suppression of AMPK activation. Therefore, berberine may be a potential therapeutic agent for the treatment of patients with cardiac myocyte injury and ischemia.

Hydroquinone (HQ), a major reactive metabolite of benzene, contributes to benzene‑induced leukemia. The molecular mechanisms that underlie this activity remain to be elucidated. Poly ADP‑ribosylation (PARylation) is a type of reversible posttranslational modification that is performed by enzymes in the PAR polymerase (PARP) family and mediates different biological processes, including apoptosis. Zona occludens 2 (ZO‑2) is a tight junction scaffold protein, which is involved in cell proliferation and apoptosis. The present study investigated the activity and mechanisms regulated by PARP‑1 during HQ‑induced apoptosis using TK6 lymphoblastoid cells and PARP‑1‑silenced TK6 cells. The results revealed that exposure to 10 µM HQ for 72 h induced apoptosis in TK6 cells and that apoptosis was attenuated in PARP‑1‑silenced TK6 cells. In cells treated with HQ, inhibition of PARP‑1 increased the expression of B cell leukemia/lymphoma 2 (Bcl‑2), increased ATP production and reduced reactive oxygen species (ROS) production relative to the levels observed in cells treated with HQ alone. Co‑localization of ZO‑2 and PAR (or PARP‑1 protein) was determined using immunofluorescence confocal microscopy. The findings of the present study revealed that ZO‑2 was PARylated via an interaction with PARP‑1, which was consistent with an analysis of protein expression that was performed using western blot analysis, which determined that ZO‑2 protein expression was upregulated in HQ‑treated control cells and downregulated in HQ‑treated PARP‑1‑silenced TK6 cells. These findings indicated that prolonged exposure to a low dose of HQ induced TK6 cells to undergo apoptosis, whereas inhibiting PARP‑1 attenuates cellular apoptosis by activating Bcl‑2 and energy‑saving processes and reducing ROS. The present study determined that PARP‑1 was involved in HQ‑induced apoptosis by PARylation of ZO‑2.

Endometrial carcinoma is the most common malignancy of the female genital tract and is the fourth most common malignancy among women worldwide. Endometrial adenocarcinoma (EAC) accounts for ~80% of endometrial carcinoma cases. Numerous critical genetic events have been determined to serve an essential role in EAC progression; however, the precise molecular mechanisms underlying EAC progression remain unclear. Pyrosequencing and methylation‑specific PCR were used to detect the methylation status of Wnt inhibitory factor 1 (WIF1). Immunohistochemistry and western blot were used to detect the expression of WIF1, Wnt family member 1 and other related pathways. The anticancer role of WIF1 in EAC was investigated in vitro and in vivo. Two of the three EAC cases exhibited significantly high methylation in five CpG sites, and the WIF1 methylation rate in EAC and endometrial tissues was 43.4 and 8%, respectively (P<0.05). The kappa consistency coefficient was ‑0.369 between methylation and mRNA expression (P<0.05) and WIF1 expression levels were significantly downregulated in EAC tissues compared with non‑tumorous tissues (P<0.01). The 5‑year overall survival rates were significantly lower for patients with tumors that negatively expressed WIF1 when compared with the 77.9% exhibited by those with positive WIF1 expression. Furthermore, the proliferation rate of KLE cells was significantly reduced following 5‑aza‑20‑deoxycytidine treatment or WIF1 overexpression in vitro and in vivo, which may be associated with downregulated c‑Myc and phosphorylated‑extracellular signal‑regulated kinase expression. These results demonstrated the important role of WIF1 in EAC tumorigenesis, and suggested that WIF1 may be a potential drug target in EAC treatment.

Melatonin is predominately produced and secreted by the pineal gland, and inhibits cell growth in various cancer cell lines such as colorectal cancer. However, the precise mechanisms involved have not been fully elucidated. In the present study, the potential molecular mechanism underlying the efficacy of melatonin on migration in RKO colon cancer cells was investigated. The effects of melatonin and H‑1152, a selective inhibitor of Rho‑associated protein kinase (ROCK), on the migration of RKO cells were analyzed by an in vitro wound healing assay. The localization of zonula occludens‑1 (ZO‑1) and occludin were observed by immunofluorescence. Reverse transcription‑quantitative polymerase chain reaction (qPCR) was performed to analyze the relative mRNA levels of ROCK, ZO‑1 and occludin. In addition, western blot analysis was implemented to examine the expression of ROCK, phospho (p)‑myosin phosphatase targeting subunit 1 (MYPT1), p‑myosin light chains (MLC) and p‑p38. The results revealed that the expression levels of ROCK2, p‑MYPT1 and p‑MLC in RKO cells were decreased, and the membrane protein expression of ZO‑1 and occludin increased when the cells were treated with melatonin. qPCR demonstrated that melatonin downregulated ROCK2 gene expression, and upregulated the expression of the ZO‑1 and occludin genes. The levels of ZO‑1 and occludin localized in the tight junctions were markedly increased in the immunofluorescence assay. In addition, the phosphorylation levels of p38 were reduced when the cells were treated with melatonin, and treatment with H‑1152 downregulated p38 phosphorylation. The results indicated that melatonin may inhibit the migration of RKO colon cancer cells by downregulating ROCK expression via the p38/mitogen‑activated protein kinase signaling pathway.

The present study aimed to investigate the effect of α7 nicotinic acetylcholine receptor (α7nAChR) agonist on the damage of hippocampal neurons and the expression of toll like receptor 4 (TLR4)/myeloid differentiation primary response 88 (Myd88)/nuclear factor (NF)‑κB signal pathway‑associated factors in cardiopulmonary bypass (CPB). Sprague Dawley rats were randomly divided into five groups: Sham operation (Sham); CPB; CPB + α7nAChR agonist PHA568487 (PHA); CPB + α7nAChR inhibitor MLA (MLA); and CPB + PHA568487 + TLR4 antagonist (CPT). Blood and brain tissue samples were harvested at 12 h following the withdrawal of CPB. Levels of serum inflammatory factors [interleukin (IL)‑1β, IL‑6 and tumor necrosis factor (TNF)‑α] and brain injury markers [S‑100β and neuron‑specific enolase (NSE)] were measured using ELISA. In addition, pathological histology and apoptosis changes were observed using hematoxylin and eosin staining, and Tunnel assays. Quantitative polymerase chain reaction and western blot assays were used to determine the expression of TLR4, Myd88 and NF‑κB mRNA, and protein in the hippocampus. The morphology of hippocampal pyramidal cells in the Sham group was observed to be normal. Pyramidal cells in the CPB, MLA and CPT groups were loosely arranged, and the baselines had disappeared, with clear nucleus pyknosis and neuronal apoptosis. Furthermore, the cells in the PHA group were slightly damaged. IL‑1β, IL‑6, TNF‑α, S‑100β and NSE expression levels in the CPB, MLA, and CPT groups were significantly higher compared with that in the Sham group (P<0.05). Compared with CPB group, the expression of inflammatory cytokines in the PHA group was significantly lower (P<0.05). The expression of TLR4, Myd88 and NF‑κB mRNA, and protein in the hippocampus of CPB, MLA and CPT groups were significantly higher compared with that in the Sham group, and the PHA group expression was significantly lower compared with the CPB group (P<0.05). α7nAChRs agonist can inhibit the apoptosis of rat brain neurons induced by CPB, and may protect against brain injury through the TLR4/Myd88/NF‑κB signaling pathway.

In the present study, the expression of Beclin 1 in osteoarthritis (OA) cartilage tissue was investigated, and also its role in proliferation, apoptosis and expression of matrix metalloproteinases (MMPs) in chondrocytes obtained from patients with OA. Beclin 1 expression in cartilage tissue from OA patients, and in the age- and sex-matched controls, was detected by immunohistochemistry, semi-quantitative polymerase chain reaction and western blotting. Chondrocytes were divided into control and Beclin 1-overexpressed groups. After transfection for 48, 72 and 96 h, cell viability, apoptosis, the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway and MMPs were examined. The mRNA and protein expression levels of Beclin 1 were significantly decreased in cartilage tissue from OA patients compared with the sex- and age-matched controls (P<0.05). In chondrocytes from OA patients, Beclin 1 overexpression significantly increased cell viability (P<0.05). Beclin 1 overexpression additionally decreased the degree of apoptosis, as demonstrated by Hoechst staining and flow cytometric analysis. B-cell lymphoma-2 (Bcl-2) was upregulated, and Bcl-2 associated X was downregulated, following Beclin 1 overexpression (P<0.05). The PI3K/Akt/mTOR signaling pathway was mitigated following Beclin 1 overexpression (P<0.05). In addition, MMP1, MMP3 and MMP13 were downregulated after Beclin 1 overexpression (P<0.05). Taken together, low expression levels of Beclin 1 may contribute towards the degeneration of chondrocytes. Beclin 1 overexpression increased cell viability, inhibited apoptosis and MMPs, likely via the PI3K/Akt/mTOR signaling pathway.

Infections by pathogens may lead to cardiovascular diseases, including acute/chronic myocarditis. (Coxsackieviruses B3) CVB3 is considered to be the most common causative agent in m‑yocarditis, which can lead to dilated cardiomyopathy. The present study aimed to investigate the mechanism of CVB3‑infected myocardial microvascular endothelial cells. The CVB3 infection was detected by 50% tissue culture infective dose (TCID50). The role of fractalkine (FKN) in the infection was detected using western blotting and RNA interference. To assess mitogen‑activated protein kinase signaling activity, levels of total and phosphorylated extracellular signal‑regulated kinase (ERK)1/2, c‑Jun N‑terminal kinase, and p38 were measured at 0, 20, 40, and 60 min after CVB3 infection by western blot analysis. The results showed that infection activated FKN via the ERK1/2 signaling pathway. Furthermore, the TCID50 of CVB3 in infected cells was lower compared with that in myocardial microvascular endothelial cells following ERK1/2 inhibition and FKN silencing. CVB3 infection of myocardial microvascular endothelial cells activates FKN via the ERK1/2 signaling pathway. These findings represent a foundation for the development of novel methods of treating CVB3‑induced myocarditis.