In this study, the protective effects of pseudoginsengenin DQ (PDQ) on cisplatin (CDDP)-induced nephrotoxicity were assessed, with a primary investigation into the mechanisms involved. Our results showed that pretreatment with PDQ remarkably restored levels of blood urea nitrogen (BUN) and creatinine (CRE), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β). Meanwhile, PDQ decreased the CDDP-induced overexpression of heme oxygenase 1 (HO-1), cytochrome P450 E1 (CYP2E1), TNF-α, nuclear factor-kappa B (NF-κB), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) in renal tissues. Hoechst 33258 and TdT-mediated dUTP nick-end labeling (TUNEL) staining showed that CDDP-induced renal tubular cell apoptosis was apparently inhibited by PDQ. Western blotting showed that PDQ reversed the CDDP-induced (1) downregulation of Sirtuin-1 (Sirt-1), nuclear-related factor 2 (Nrf2), and Bcl-2, and (2) upregulation of NF-κB, Nox-4, Bax, caspase-9, and caspase-3. In addition, PDQ enhanced the antitumor activity of cisplatin in Lewis lung cancer xenograft tumor model mice. In conclusion, we found that PDQ exerted a renal protective effect against CDDP-induced acute nephrotoxicity via Sirt1/NF-κB and the caspase signaling pathway without compromising the antitumor activity of CDDP, which provides a new potential strategy for the clinical treatment of cancer and presents a new medicinal application of PDQ.

In the present study, the in vitro cytotoxicity of daidzein was evaluated in human BEL-7402, A549, HeLa, HepG-2 and MG-63 cancer cell lines. BEL-7402 cells were sensitive to daidzein treatment, with an IC50 value of 59.7±8.1 µM. Daidzein showed no cytotoxic activity toward A549, HeLa, HepG-2 and MG-63 cells. Daidzein increased the levels of reactive oxygen species (ROS) and induced a decrease in mitochondrial membrane potential. Morphological and comet assays showed that daidzein effectively induced apoptosis in BEL-7402 cells. Additionally, daidzein caused cell cycle arrest at the G2/M phase in the BEL-7402 cell line. Daidzein downregulated the expression of Bcl-2, Bcl-x and Baid proteins and upregulated the levels of Bim protein in the BEL-7402 cells. The results demonstrated that daidzein induced BEL-7402 cell apoptosis through an ROS-mediated mitochondrial dysfunction pathway.

Transmissible gastroenteritis virus (TGEV) has been reported to induce apoptosis in swine testis (ST) cells. However, the mechanisms underlying TGEV-induced apoptosis are still unclear. In this study we observed that TGEV infection induced apoptosis in porcine kidney (PK-15) cells in a time- and dose-dependent manner. TGEV infection up-regulated FasL, activated FasL-mediated apoptotic pathway, leading to activation of caspase-8 and cleavage of Bid. In addition, TGEV infection down-regulated Bcl-2, up-regulated Bax expression, promoted translocation of Bax to mitochondria, activated mitochondria-mediated apoptotic pathway, which in turn caused the release of cytochrome c and the activation of caspase-9. Both extrinsic and intrinsic pathways activated downstream effector caspase-3, followed by the cleavage of PARP, resulting in cell apoptosis. Moreover, TGEV infection did not induce significant DNA fragmentation in ammonium chloride (NH(4)Cl) pretreated PK-15 cells or cells infected with UV-inactivated TGEV. In turn, block of caspases activation also did not affect TGEV replication. Taken together, this study demonstrates that TGEV-induced apoptosis is dependent on viral replication in PK-15 cells and occurs through activation of FasL- and mitochondria-mediated apoptotic pathways.

Although previous studies have reported that saponins (ginsenosides, the major active and most representative ingredients in Panax ginseng C.A. Meyer) exerted a good ameliorative effect on cisplatin (CP)-induced acute kidney injury in animal models, little attention has been paid to a large number of polysaccharides isolated and purified from ginseng. This work aimed to investigate the protective effect and the possible molecular mechanism of ginseng polysaccharide (WGP) on CP-induced kidney toxicology in mice. The results from biomarker analysis including serum creatinine (CRE) and blood urea nitrogen (BUN) confirmed the protective effect of WGP at 200 and 400 mg/kg on CP-induced renal-toxicology. We found that WGP reduces the apoptosis of kidney cells by inhibiting endoplasmic reticulum (ER) stress caused by CP, which is manifested by increased phosphorylation of PERK. In addition, the apoptosis-associated with caspase 3 activation in renal cells induced by CP was inhibited after administration of WGP, and the phosphorylation levels of PI3K and AKT were also reduced significantly. We also demonstrated that after exposure to CP, the unfolded protein response signaling pathway PERK-eIF2α-ATF4 axis was significantly activated, manifested by increased phosphorylation of eIF2α and increased expression of ATF4 and CHOP. Interestingly, the WGP administration improves this situation. Furthermore, the supplement of WGP inhibited the overexpression of nuclear factor-kappa B p65 (NF-κB p65) and tumor necrosis factor-α (TNF-α) caused by CP exposure. In short, for the first time, our findings indicated that WGP could effectively prevent CP-induced ER stress, inflammation, and apoptosis in renal cells, in part, by regulating the PI3K/AKT and PERK-eIF2α-ATF4 signaling pathways.

Early brain injury is considered to be a primary reason for the poor prognosis of patients suffering from subarachnoid hemorrhage (SAH). Due to its pro-inflammatory activity, cold-inducible RNA-binding protein (CIRP) has been implicated in the ischemic brain insult, but its possible interplay with hypothermia in SAH treatment remains to be evaluated. One-hundred and thirty-eight Sprague-Dawley rats (300-350 g males) were randomly allocated into the following groups: sham-operated (Sham); SAH; and SAH + hypothermia (SAH + H), each comprised of 46 animals. After treatments, the brain tissues of the three groups were randomly collected after 12 h, 1 d, 3 d, and 7 d, and the expression levels of the CIRP and mitochondrial apoptosis pathway-related proteins Bax, Bcl-2, caspase-9, caspase-3, and cytochrome c measured using Western blotting and real-time PCR. Brain damage was assessed by TUNEL and Nissl staining, the electron microscopy of brain tissue slices as well as functional rotarod tests. Expression of CIRP, Bax, caspase-9, caspase-3, and cytochrome c as well as reduced motor function incidence were higher in the SAH group, particularly during the first 3 d after SAH induction. Hypothermia blunted these SAH responses and apoptosis, thereby indicating reduced inflammatory signaling and less brain cell injury in the early period after SAH. Hypothermia treatment was found to effectively protect the brain tissue from early SAH injury in a rat model and its further evaluation as a therapeutic modality in SAH patients requires further study.

Background and Objective: The incidence of chronic kidney disease (CKD) is steadily increasing. Although renal tubular epithelium injury is closely correlated with the prognosis of CKD, the underlying mechanism is not fully understood and therapeutic strategies are limited. The main bioactive component of the Chinese medicine herb, glycyrrhiza, is 18α-glycyrrhetinic acid (Ga), which is also a pharmacological inhibitor of gap junctions. Our previous studies indicated that Ga is able to ameliorate renal cell injury. The present study explored the regulatory role of Ga in redox signaling in renal tubular epithelial cells with oxidative injury. Methods: Rat renal tubular epithelial cells, NRK-52E, were incubated with Px-12, a thioredoxin inhibitor, to mimic thioredoxin deficiency and induce oxidative injury in vitro. A Cell Counting Kit-8 was used to analyze cell viability while a reactive oxygen species (ROS)/superoxide (O2 -) fluorescence probe was employed to determine oxidative stress. Apoptosis was evaluated using DT-mediated dUTP nick end labeling/4,6-diamidino-2-phenylindole staining and cleaved caspase 3 protein analysis. Western blot analysis was used to analyze the expression of specific proteins while siRNA transfection was performed to downregulate targeted proteins. Results: Inhibition of thioredoxin 1 by Px-12 triggered renal tubular cell oxidative injury as evidenced by morphological change, loss of cellular viability, over production of ROS and O2 -, and appearance of cleaved caspase-3. Ga significantly attenuated cell oxidative injury, as indicated by the parameters mentioned above. Px-12 induced phosphorylation of c-Jun N-terminal kinase (JNK) and subsequently the expression of connexin 43 (Cx43) in NRK-52E cells. Ga and the JNK inhibitor, sp600125, markedly suppressed Px-12-induced generation of intracellular ROS and O2 -. Inhibition of JNK improved Px-12-elicited NRK-52E cell injury. Moreover, sp600125 inhibited Cx43 expression. After downregulation of Cx43 via Cx43 siRNA transfection, the phosphorylation of JNK was markedly reduced. Furthermore, Ga restored the expression of thioredoxin 1 inhibited by Px-12. Conclusion: ROS-JNK-Cx43-thioredoxin 1 signaling plays a crucial role in renal tubular cell injury. JNK is involved in the regulation of thioredoxin 1 and Cx43, and Cx43 reciprocally regulates thioredoxin 1. Inhibition of gap junctions by Ga alleviated renal tubular oxidative injury via improvement of thioredoxin 1-mediated redox signaling.

Deguelin, a natural rotenoid isolated from several plants, has been reported to exert anti-tumour effects in various cancers. However, the molecular mechanism of this regulation remains to be fully elucidated. Here, we found that deguelin inhibited the growth of non-small cell lung cancer (NSCLC) cells both in vitro and in vivo by downregulation of Bmi1 expression. Our data showed that Bmi1 is highly expressed in human NSCLC tissues and cell lines. Knockdown of Bmi1 significantly suppressed NSCLC cell proliferation and colony formation. Deguelin treatment attenuated the binding activity of Bmi1 to the Noxa promoter, thus resulting in Noxa transcription and apoptosis activation. Knockdown of Bmi1 promoted Noxa expression and enhanced deguelin-induced apoptosis, whereas overexpression of Bmi1 down-regulated Noxa protein level and deguelin-induced apoptosis. Overall, our study demonstrated a novel apoptotic mechanism for deguelin to exert its anti-tumour activity in NSCLC cells.

Under some occupational conditions, workers are inevitably exposed to high-intensity radiofrequency (RF) fields. In this study, we investigated the effects of one-month exposure to a 220 MHz pulsed modulated RF field at the power density of 50 W/m² on the sperm quality in male adult rats. The sperm quality was evaluated by measuring the number, abnormality and survival rate of sperm cells. The morphology of testis was examined by hematoxylin-eosin (HE) staining. The levels of secreting factors by Sertoli cells (SCs) and Leydig cells (LCs) were determined by enzyme linked immunosorbent assay (ELISA). The level of cleaved caspase 3 in the testis was detected by immunofluorescence staining. Finally, the expression levels of the apoptosis-related protein (caspase 3, BAX and BCL2) in the testis were assessed by Western blotting. Compared with the sham group, the sperm quality in the RF group decreased significantly. The levels of secreting factors of SCs and the morphology of the testis showed an obvious change after RF exposure. The level of the secreting factor of LCs decreased significantly after RF exposure. The levels of cleaved caspase 3, caspase 3, and the BAX/BCL2 ratio in the testis increased markedly after RF exposure. These data collectively suggested that under the present experimental conditions, 220 MHz pulsed modulated RF exposure could impair sperm quality in rats, and the disruption of the secreting function of LCs and increased apoptosis of testis cells induced by the RF field might be accounted for by this damaging effect.

We investigated the effect of 1.4% isoflurane (ISO) on the development of inflammation and apoptosis caused by zymosan (ZY) in mice. We found that ZY-challenged mice exhibited significant body weight loss, markedly high mortality, and significant lung injury characterized by the deterioration of histopathology, histologic scores, and wet-to-dry ratio after ISO treatment. ISO dramatically attenuated ZY-induced lung neutrophil recruitment and inflammation, as evidenced by the reduced levels of total cells, neutrophils, and proinflammatory cytokines (i.e., tumor necrosis factor- α , interleukin- (IL-) 1 β , IL-6, and macrophage inflammatory protein-2) in bronchoalveolar lavage fluid and of their mRNA expression in lung tissues. ISO also inhibited ZY-induced expression and activation of nuclear factor-kappaB p65 and inducible nitric oxide synthase in pulmonary tissue. ZY administration also resulted in the upregulation of heme oxygenase-1 expression and activity in the lung, which was further enhanced by ISO treatment. Moreover, ISO markedly prevented ZY-induced pulmonary cell apoptosis in mice, as reflected by the decrease in expression of procaspase-8, procaspase-3, cleaved caspase-8, and cleaved caspase-3, as well as in caspase-3 activity and Bcl-2-associated X/B-cell lymphoma 2 ratio. These results indicate that ISO is a potential therapeutic drug for treating ZY-induced lung injury, and further investigations are warranted.

Ganoderma lucidum polysaccharides have protective effects against apoptosis in neurons exposed to ischemia/reperfusion injury, but the mechanisms are unclear. The goal of this study was to investigate the underlying mechanisms of the effects of ganoderma lucidum polysaccharides against oxidative stress-induced neuronal apoptosis. Hydrogen peroxide (H2O2) was used to induce apoptosis in cultured cerebellar granule cells. In these cells, ganoderma lucidum polysaccharides remarkably suppressed H2O2-induced apoptosis, decreased expression of caspase-3, Bax and Bim and increased that of Bcl-2. These findings suggested that ganoderma lucidum polysaccharides regulate expression of apoptosis-associated proteins, inhibit oxidative stress-induced neuronal apoptosis and, therefore, have significant neuroprotective effects.

The NLRP3 inflammasome plays an important role in protecting the host from infection and aseptic inflammation, and its regulatory mechanism is not completely understood. Dysregulation of NLRP3 can cause diverse inflammatory diseases. HECTD3 is a E3 ubiquitin ligase of the HECT family that has been reported to participate in autoimmune and infectious diseases. However, the relationship between HECTD3 and the NLRP3 inflammasome has not been well studied. Herein, we show that HECTD3 blocks the interaction between NEK7 and NLRP3 to inhibit NLRP3 inflammasome assembly and activation. In BMDMs, Hectd3 deficiency promotes the assembly and activation of NLRP3 inflammasome and the secretion of IL-1β, while the overexpression of HECTD3 inhibits these processes. Unexpectedly, HECTD3 functions in an E3 activity independent manner. Mechanically, the DOC domain of HECTD3 interacts with NACHT/LRR domain of NLRP3, which blocks NLRP3-NEK7 interaction and NLRP3 oligomerization. Furthermore, HECTD3 inhibits monosodium urate crystals (MSU)-induced gouty arthritis, a NLRP3-related disease. Thus, we reveal a novel regulatory mechanism of NLRP3 by HECTD3 and suggest HECTD3 could be a potential therapeutic target for NLRP3-dependent pathologies.

Apoptosis has been proven to play a crucial role in early brain injury pathogenesis and to represent a target for the treatment of subarachnoid hemorrhage (SAH). Previously, we demonstrated that astaxanthin (ATX) administration markedly reduced neuronal apoptosis in the early period after SAH. However, the underlying molecular mechanisms remain obscure. In the present study, we tried to investigate whether ATX administration is associated with the phosphatidylinositol 3-kinase-Akt (PI3K/Akt) pathway, which can play an important role in the signaling of apoptosis. Our results showed that post-SAH treatment with ATX could cause a significant increase of phosphorylated Akt and Bad levels, along with a significant decrease of cleaved caspase-3 levels in the cortex after SAH. In addition to the reduced neuronal apoptosis, treatment with ATX could also significantly reduce secondary brain injury characterized by neurological dysfunction, cerebral edema and blood-brain barrier disruption. In contrast, the PI3K/Akt inhibitor, LY294002, could partially reverse the neuroprotection of ATX in the early period after SAH by downregulating ATX-induced activation of Akt/Bad and upregulating cleaved caspase-3 levels. These results provided the evidence that ATX could attenuate apoptosis in a rat SAH model, potentially, in part, through modulating the Akt/Bad pathway.

Intestinal ischemia/reperfusion (IIR) is a common pathological event associated with intestinal injury and apoptosis with high mortality. Nuclear factor (NF)-E2-related factor-2 (Nrf2) is a key transcription factor that interacts with NF-κB and has a vital anti-inflammatory effect. However, whether Nrf2 has a role in IIR-induced apoptosis and the possible underlining mechanisms, such as modulation of the inflammation regulation pathway, have remained to be fully elucidated. In the present study, IIR was identified to cause significant intestinal injury and apoptosis, with high expression levels of inflammatory cytokines, as well as the apoptotic proteins B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax) and caspase-3, while simultaneously decreasing the protein levels of Bcl-2. The effect was more pronounced after pretreatment of the animals with all-trans retinoic acid or brusatol, potent inhibitors of Nrf2. t-Butylhydroquinone, an Nrf2 activator, significantly attenuated IIR-induced intestinal injury and apoptosis, with inhibition of the overexpression of the inflammatory cytokines, Bax and caspase-3 protein and partial restoration of Bcl-2 protein expression. Taken together, these results indicated that increased Nrf2 expression reduced IIR-induced intestinal apoptosis and that the protective function of Nrf2 may be based on its anti-inflammatory effects through the inhibition of the NF-κB pathway.

Overexpression of survivin is frequently observed in human malignancies and is associated with poor prognosis. The present study found that survivin is highly expressed in nasopharyngeal carcinoma (NPC) tumor tissues. Depleting survivin with shRNA inhibited cell viability, colony formation, and in vivo tumorigenesis of NPC cells. With a natural product screening, we identified Butein as a potential anti-tumor compound for NPC by reducing survivin protein level. Butein shortened the half-life of survivin and enhanced ubiquitination-mediated degradation. The mechanism study showed that Butein promoted the interaction between survivin and E3 ligase Fbxl7, and the knockdown of Fbxl7 compromised Butein-induced survivin ubiquitination. Butein suppressed the Akt-Wee1-CDK1 signaling and decreased survivin Thr34 phosphorylation, facilitating E3 ligase Fbxl7-mediated survivin ubiquitination and degradation. Moreover, Butein exhibited a strong in vivo anti-tumor activity, as the tumor volume of Butein-treated xenografts was reduced significantly. Butein alone or combined with cisplatin (CDDP) overcame chemoresistance in NPC xenograft tumors. Overall, our data indicate that Butein is a promising anti-tumor agent for NPC treatment.

Swainsonine (1, 2, 8-trihyroxyindolizidine, SW), a natural alkaloid, has been reported to exhibit anti-cancer activity on several mouse models of human cancer and human cancers in vivo. However, the mechanisms of SW-mediated tumor regression are not clear. In this study, we investigated the effects of SW on several human lung cancer cell lines in vitro. The results showed that SW significantly inhibited these cells growth through induction of apoptosis in different extent in vitro. Further studies showed that SW treatment up-regulated Bax, down-regulated Bcl-2 expression, promoted Bax translocation to mitochondria, activated mitochondria-mediated apoptotic pathway, which in turn caused the release of cytochrome c, the activation of caspase-9 and caspase-3, and the cleavage of poly (ADP-ribose) polymerase (PARP), resulting in A549 cell apoptosis. However, the expression of Fas, Fas ligand (FasL) or caspase-8 activity did not appear significant changes in the process of SW-induced apoptosis. Moreover, SW treatment inhibited Bcl-2 expression, promoted Bax translocation, cytochrome c release and caspase-3 activity in xenograft tumor cells, resulting in a significant decrease of tumor volume and tumor weight in the SW-treated xenograft mice groups in comparison to the control group. Taken together, this study demonstrated for the first time that SW inhibited A549 cancer cells growth through a mitochondria-mediated, caspase-dependent apoptotic pathway in vitro and in vivo.

Wear particle-induced periprosthetic osteolysis is the main cause of aseptic loosening of orthopaedic implants. The aim of this study is to determine the protective effect of quercetin (QUE) against titanium (Ti) particle-induced ERS-related apoptosis and osteolysis. In this study, RAW264.7 cells were pretreated with different concentrations (40, 80, and 160 μmol/l) of QUE for 30 min and then treated with Ti particle (5 mg/ml) for 24 h. Cell viability and apoptosis were determined using MTT assay and Annexin V-FITC apoptosis detection kit, respectively. Protein and mRNA expressions of ERS-related genes were examined by western blot and real-time PCR, respectively. The release of inflammatory cytokines was detected by ELISA. Then a mouse calvarial osteolysis model was established. Histological sections of calvaria were stained with H&E or TRAP. The results showed that Ti particle reduced cell viability and induced apoptosis in RAW264.7 macrophages. The cytotoxic effects of Ti particle were dramatically inhibited by QUE pretreatment. Interestingly, we found that QUE also significantly reduced Ti particle-induced up-regulation of the expression levels of PERK, IRE1, GRP78, CHOP, caspase-12 and caspase-3 and enhanced the down-regulation of Bcl-2. In addition, QUE decreased Ti particle-induced inflammatory cytokines release from RAW264.7 cells. Moreover, treatment with QUE markedly decreased osteoclast number. In a mouse calvarial osteolysis model, QUE inhibited Ti particle-induced osteolysis in vivo by inhibiting osteoclast formation and expressions of ERS-related genes. In conclusion, QUE can protect RAW264.7 cells from Ti particle-induced ERS-related apoptosis and suppress calvarial osteolysis in vivo.

To investigate whether the abscopal effects of cranial irradiation (C-irradiation) cause testicular damage in mice, male C57BL/6 mice (9weeks of age) were randomly divided into a sham irradiation group, a shielded group and a C-irradiation group and administered sham/shielded irradiation or C-irradiation at a dose rate of 2.33Gy/min (5Gy/d for 4 d consecutively). All mice were sacrificed at 4weeks after C-irradiation. We calculated the testis index, observed testicular histology by haematoxylin-eosin (HE) staining and observed testicular ultrastructure by transmission electron microscopy. Western blotting was used to determine the protein levels of Bax, Bcl-2, Cleaved caspase 3, glial cell line-derived neurotrophic factor (GDNF) and stem cell factor (SCF) in the testes of mice. Immunofluorescence staining was performed to detect the expression of Cleaved caspase 3 and 3β hydroxysteroid dehydrogenase (3βHSD), and a TUNEL assay was used to confirm the location of apoptotic cells. The levels of testosterone (T), GDNF and SCF were measured by ELISA. We also evaluated the sperm quality in the cauda epididymides by measuring the sperm count, abnormality, survival rate and apoptosis rate. The results showed that there was no significant difference in testicular histology, ultrastructure or sperm quality between the shielded group and sham group. Compared with the sham/shielded group, the C-irradiation group exhibited a lower testis index and severely damaged testicular histology and ultrastructure at 4weeks after C-irradiation. The levels of apoptosis in the testes increased markedly in the C-irradiation group, especially in spermatogonial stem cells. The levels of serum T and testicular 3βHSD did not obviously differ between the sham group and the C-irradiation group, but the levels of GDNF and SCF in the testes increased in the C-irradiation group, compared with the sham group. In addition, the sperm count and survival rate decreased in the C-irradiation group, while the abnormality and apoptosis rate increased. Under these experimental conditions, the abscopal effects of C-irradiation induced testicular damage with regard to both structure and function and ultimately decreased sperm quality in mice. These findings provide novel insights into prevention and treatment targets for male reproductive damage induced by C-irradiation.

Cisplatin, a potent anticancer drug, is usually causing nephrotoxicity; limiting its therapeutic application and efficiency. Maltol may be used to prevent such toxic effect. The aim of this study was to investigate the underlying protective mechanisms of maltol on nephrotoxicity by cisplatin using a cisplatin-treated mouse model and a cellular toxicity model of HEK293 cells. The blood urea nitrogen (BUN), creatinine (CRE) and neutrophil gelatinase-associated lipocalin (NGAL) levels in mice were increased by cisplatin but decreased to normal ranges by maltol pretreatment (50 and 100 mg/kg) for ten days. Besides, maltol pretreatment decreased oxidative stress, lipid peroxidation and apoptosis in cisplatin-treated mice. The inhibitory action of maltol on inflammatory responses was achieved by reducing the expressions in NF-κB, IL-1β, iNOS, and TNF-α in the mice in vivo. Additionally, maltol restored the reduction of PI3K/Akt and mTOR levels by cisplatin through increasing AMPK expression in cisplatin-treated HEK293 cells. Maltol also suppressed the expression of Bax and caspase 3 by inhibiting the p53 activity in HEK293 cells. Overall, maltol may serve as a valuable potential drug to prevent cisplatin-induced nephrotoxicity, and the underlying molecular mechanisms of maltol action may involve intracellular AMPK/PI3K/Akt and p53 signaling pathways.

To compare the treatment effects and tolerability of a topical application of mizoribine (MZR) and cyclosporine A (CsA) eye drops (Restasis; Allergan, Inc., Irvine, CA, USA) in a mouse dry eye model.

Rottlerin is a natural polyphenolic compound that was initially indicated as a PKCδ inhibitor. However, it was recently revealed that it may target a number of molecules and have biological effects on various cell types and is considered as a possible agent for tumor and cell proliferative diseases. Psoriasis is a chronic inflammatory cutaneous disorder with undefined etiology and is characterized by abnormal cellular proliferation, angiogenesis, and inflammation. Therefore, this paper investigates the regulatory effects of rottlerin on normal human epidermal keratinocytes (NHEKs) and imiquimod (IMQ)-induced psoriasiform (IPI) lesions. In vitro results showed that rottlerin inhibited cell proliferation in NHEKs through growth arrest and NFκB inhibition. It may also induce apoptosis in an autophagy-dependent pathway. We found that rottlerin inhibited human microvascular endothelial cells tube formation on matrigel. Rottlerin also decreased the cell senescence of keratinocytes and intracellular ROS generation, which indicated its antioxidant effect. We also showed that rottlerin affects the expression of keratinocyte proliferation biomarkers. In 12-O-tetradecanoylphorbol13-acetate (TPA)-induced keratinocytes, rottlerin significantly inhibited the expression of the induced pro-inflammatory cytokines in keratinocytes. An animal experiment provided the corresponding evidence based on this evidence in vitro, by using IPI model, we found that rottlerin could relieve the psoriasiform of BALB/c mice by inhibiting keratinocyte proliferation, inflammatory cell infiltration, and vascular proliferation. In conclusion, our results suggest that rottlerin may prove useful in the development of therapeutic agents against psoriasis. However, the deep mechanism still requires further study.