Koumine inhibits IL-1ß-induced chondrocyte inflammation and ameliorates extracellular matrix degradation in osteoarthritic cartilage through activation of PINK1/Parkin-mediated mitochondrial autophagy.

Osteoarthritis (OA) is a degenerative joint disease, Increasingly, mitochondrial autophagy has been found to play an important regulatory role in the prevention and treatment of osteoarthritis. Koumine is a bioactive alkaloid extracted from the plant Gelsemium elegans. In previous research, Koumine was found to have potential in improving the progression of OA in rats. However, the specific mechanism of its action has not been fully explained. Therefore, the aim of this study was to investigate whether Koumine can alleviate OA in rats by influencing mitochondrial autophagy. In the in vitro study, rat chondrocytes (RCCS-1) were induced with IL-1ß (10 ng/mL) to induce inflammation, and Koumine (50 µg/mL) was co-treated. In the in vivo study, a rat OA model was established by intra-articular injection of 2% papain, and Koumine was administered orally (1 mg/kg, once daily for two weeks). It was found that Koumine effectively reduced cartilage erosion in rats with osteoarthritis. Additionally, it decreased the levels of inflammatory factors such as IL-1ß, IL-6, and extracellular matrix (ECM) components MMP13 and ADAMTS5 in chondrocytes and articular cartilage tissue, while increasing the level of Collagen II.Koumine inhibited the production of reactive oxygen species (ROS) in cartilage tissue and increased the number of autophagosomes in chondrocytes and articular cartilage tissue. Additionally, it upregulated the expression of mitochondrial autophagy proteins LC3Ⅱ/Ⅰ, PINK1, Parkin, and Drp1. The administration of Mdivi-1 (50 µM) reversed the enhanced effect of Koumine on mitochondrial autophagy, as well as its anti-inflammatory and anti-ECM degradation effects in rats with OA. These findings suggest that Koumine can alleviate chondrocyte inflammation and improve the progression of OA in rats by activating PINK1/Parkin-mediated mitochondrial autophagy.

Melatonin alleviates T-2 toxin-induced oxidative damage, inflammatory response, and apoptosis in piglet spleen and thymus.

T-2 toxin, an unavoidable contaminant in animal feeds, can induce oxidative stress and damage immune organs. Melatonin (MT), a natural and potent antioxidant, has shown promise as a detoxifier for various mycotoxins. However, the detoxifying effect of MT on T-2 toxin has not been previously reported. In order to investigate the protective effect of MT added to diets on the immune system of T-2 toxin-exposed piglets, twenty piglets weaned at 28d of age were randomly divided into control, T-2 toxin (1 mg/kg), MT (5 mg/kg), and T-2 toxin (1 mg/kg) + MT (5 mg/kg) groups(n = 5 per group). Our results demonstrated that MT mitigated T-2 toxin-induced histoarchitectural alterations in the spleen and thymus, such as hemorrhage, decreased white pulp size in the spleen, and medullary cell sparing in the thymus. Further research revealed that MT promoted the expression of Nrf2 and increased the activities of antioxidant enzymes CAT and SOD, while reducing the production of the lipid peroxidation product MDA. Moreover, MT inhibited the NF-κB signaling pathway, regulated the expression of downstream cytokines IL-1ß, IL-6, TNF-α, and TGF-ß1. MT also suppressed the activation of caspase-3 while down-regulating the ratio of Bax/Bcl-2 to reduce apoptosis. Additionally, MT ameliorated the T-2 toxin-induced disorders of immune cells and immune molecules in the blood. In conclusion, our findings suggest that MT may effectively protect the immune system of piglets against T-2 toxin-induced damage by inhibiting oxidative stress, inflammatory response, and apoptosis in the spleen and thymus. Therefore, MT holds the potential as an antidote for T-2 toxin poisoning.

Viola yedoensis Makino alleviates heat stress-induced inflammation, oxidative stress, and cell apoptosis in the spleen and thymus of broilers.

ETHNOPHARMACOLOGICAL RELEVANCE: Viola yedoensis Makino (VYM) is a traditional Chinese herbal medicine widely distributed in China. It has many pharmacological effects such as anti-inflammatory, immune regulation and anti-oxidation. However, the protective effect of VYM on the spleen and thymus of broilers induced by heat stress has rarely been reported. AIM OF THE STUDY: We established a heat stress model of broilers to explore the protective effect of VYM on spleen and thymus of broilers. MATERIALS AND METHODS: In this experiment, a heat stress model was made by adjusting the feeding temperature of broilers. The protective effect of VYM on the spleen and thymus of heat-stressed broilers were evaluated by detecting immune organ coefficient, histological observation, Enzyme-Linked Immunosorbent Assay, production of antioxidant enzymes and peroxides, TUNEL Staining, Quantitative Real-time PCR. RESULTS: In this study, 60 healthy male AA broilers were divided into 6 groups: Control, 4.5% VYM, HS, HS + 0.5% VYM, HS + 1.5% VYM, HS + 4.5% VYM. After 42 days of feeding, serum, spleen and thymus were collected for detection and analysis. The study revealed that heat stress can lead to pathological damage in the spleen and thymus of broilers, reduce the content of immunoglobulin and newcastle disease (ND), infectious bursal disease (IBD) antibody levels, increase the expression of inflammatory factors IL-1ß, INF-γ, heat shock 70 kDa protein (HSP70), heat shock 90 kDa protein (HSP90). Heat stress inhibits the activity of antioxidant enzymes CAT and SOD, promotes the production of MDA, and then lead to oxidative damage of the spleen and thymus. In addition, apoptotic cells and the ratio of Bax/Bcl-2 was increased. However, the addition of VYM to the feed can alleviate the adverse effects of heat stress on the spleen and thymus of broilers. CONCLUSIONS: This study showed that the addition of VYM to the diet could inhibit oxidative stress and apoptosis, and reduce the inflammatory damage of heat stress on the spleen and thymus of broilers. This study provides a basis for further exploring the regulatory role of VYM in heat stress-induced immune imbalance in broilers. In addition, this study also provides a theoretical basis for the development of VYM as a feed additive with immunomodulatory effects.

Characterizing temporal variability and repeatability of dose-dependent functional genomics approach for evaluating triclosan toxification.

Dose-dependent functional genomics approach has shown great advantage in identifying the molecular initiating event (MIE) of chemical toxification and yielding point of departure (POD) at genome-wide scale. However, POD variability and repeatability derived from experimental design (settings of dose, replicate number, and exposure time) has not been fully determined. In this work, we evaluated POD profiles perturbed by triclosan (TCS) using dose-dependent functional genomics approach in Saccharomyces cerevisiae at multiple time points (9 h, 24 h and 48 h). The full dataset (total 9 concentrations with 6 replicates per treatment) at 9 h was subsampled 484 times to generate subsets of 4 dose groups (Dose A - Dose D with varied concentration range and spacing) and 5 replicate numbers (2 reps - 6 reps). Firstly, given the accuracy of POD and the experimental cost, the POD profiles from 484 subsampled datasets demonstrated that the Dose C group (space narrow at high concentrations and wide dose range) with three replicates was best choice at both gene and pathway levels. Secondly, the variability of POD was found to be relatively robustness and stability across different experimental designs, but POD was more dependent on the dose range and interval than the number of replicates. Thirdly, MIE of TCS toxification was identified to be the glycerophospholipid metabolism pathway at all-time points, supporting the ability of our approach to accurately recognize MIE of chemical toxification at both short- and long-term exposure. Finally, we identified and validated 13 key mutant strains involved in MIE of TCS toxification, which could serve as biomarkers for TCS exposure. Taken together, our work evaluated the repeatability of dose-dependent functional genomics approach and the variability of POD and MIE of TCS toxification, which will benefit the experimental design for future dose-dependent functional genomics study.

KIF23, under regulation by androgen receptor, contributes to nasopharyngeal carcinoma deterioration by activating the Wnt/ß-catenin signaling pathway.

Our study aimed to explore the potential mechanisms of KIF23 regulating function in the progression of nasopharyngeal carcinoma and pinpoint novel therapeutic targets for the clinical treatment of nasopharyngeal carcinoma patients. Firstly, the mRNA and protein level of KIF23 in nasopharyngeal carcinoma was measured using quantitative real-time PCR and western blot. Then, the influence of KIF23 on tumor metastasis and growth in nasopharyngeal carcinoma was determined through the in vivo and in vitro experiments. Lastly, the regulatory mechanisms of KIF23 in nasopharyngeal carcinoma were illustrated in the chromatin immunoprecipitation assay. KIF23 was first found to be overexpressed in nasopharyngeal carcinoma samples, and its expression was associated with poor prognosis. Then, the nasopharyngeal carcinoma cell's proliferation, migration, and invasion potential could be improved by inducing KIF23 expression both in vivo and in vitro. Furthermore, androgen receptor (AR) was found to bind to the KIF23 promoter region directly and enhance KIF23 transcription. At last, KIF23 could accelerate nasopharyngeal carcinoma deterioration via activating the Wnt/ß-catenin signaling pathway. AR/KIF23/Wnt/ß-catenin pathway promotes nasopharyngeal carcinoma deterioration. Our findings could serve as a new therapeutic strategy for nasopharyngeal carcinoma in the clinical practice.

Citrinin Exposure Induced Testicular Damage and Spermatogenesis Disorder by Triggering Endoplasmic Reticulum Stress.

Damage to the reproductive system is the key factor leading to male infertility. Citrinin (CTN) is produced by Penicillium and Aspergillus in nature, and is definitely found in food and animal feed. Studies have revealed that CTN can cause damage to male reproductive organs and reduce fertility, but the mechanism of toxicity has not been revealed. In the present study, male Kunming mice were given different doses of CTN (0, 1.25, 5 or 20 mg/kg BW) by intragastric administration. The results demonstrated that CTN exposure caused disorder of androgen, a decline in sperm quality, and histopathological damage of testis. The inhibition of the expression of ZO-1, claudin-1 and occludin suggests that the blood-testis barrier (BTB) was damaged. Simultaneously, CTN inhibited the activity of antioxidant enzymes such as CAT and SOD, and promoted the production of MDA and ROS, resulting in oxidative damage of testis. Additionally, apoptotic cells were detected and the ratio of Bax/Bcl-2 was increased. Not only that, CTN activated the expression of endoplasmic reticulum stress (ERS)-related proteins IRE1, ATF6, CHOP, and GRP78. Interestingly, 4-Phenylbutyric Acid (4-PBA, an ERS inhibitor) treatment blocked the adverse effects of CTN exposure on male reproduction. In short, the findings suggested that CTN exposure can cause damage to mouse testis tissue, in which ERS exhibited an important regulatory role.

PI3K/AKT/mTOR, NF-κB and ERS pathway participated in the attenuation of H2O2-induced IPEC-J2 cell injury by koumine.

ETHNOPHARMACOLOGICAL RELEVANCE: Koumine, an indole alkaloid extracted from Gelsemium elegans Benth, exerts anti-inflammation and antioxidant activities. However, the effects of koumine on intestinal injury induced by H2O2 and its potential molecular mechanisms need larger studies. AIM OF THE STUDY: We established an IPEC-J2 cell damage model induced by H2O2 to explore the protective mechanism of koumine on intestinal injury. MATERIALS AND METHODS: In the experiment, cell damage models were made with hydrogen peroxide. To assess the protective effect of koumine on H2O2-induced IPEC-J2 cell injury, CCK-8, the release of LDH and ROS, transmission electron microscopy and Annexin V-FITC/PI were employed. Western Blot and Quantitative Real-time PCR were used to determine the potential alleviated mechanism of koumine on H2O2-trigged IPEC-J2 cell damage. RESULTS: The results of CCK-8 and LDH implied that koumine has a mitigative effect on H2O2-induced cell damage via upregulating cell viability and suppressing cell membrane fragmentation. Simultaneously, koumine notably inhibited the level of pro-inflammatory factors (IL-1ß, IL-6, IL-8, TNF-α and TGF-ß), the over-production of ROS along with decreasing the injury of mitochondrion, endoplasmic reticulum and lysosome induced by H2O2. Moreover, koumine dramatically attenuated H2O2-triggered IPEC-J2 cell apoptosis and autophagy. Subsequently, Western blot analysis identified NF-ΚB, PI3K and ERS as possible pathway responsible for the protective effect of koumine on H2O2-stimulated IPEC-J2 cell inflammation. CONCLUSIONS: This in vitro experimental study suggests that koumine suppresses the H2O2-induced activation of inflammatory pathways, oxidative injury, ER stress, apoptosis and autophagy, which provide a rationale for therapeutically use in major intestinal diseases.

Betulinic acid alleviates zearalenone-induced uterine injury in mice.

Zearalenone (ZEA) is a mycotoxin with estrogen-like biological activity, which widely present in feed and raw materials, with strong reproductive system toxicity and a major threat to animal reproduction. Betulinic acid (BA) is a natural plant compound with antioxidant, anti-inflammatory and other pharmacological activities. However, the mechanism of ZEA-induced uterine injury and the protective effect of BA have not been reported. Our results show that ZEA could cause uterine histopathological damage and cellular ultrastructural damage, affecting the secretion of sex hormones, such as estradiol (E2) and progesterone (P4), and increase the mRNA and protein expression of estrogen receptor α (ERα). ZEA could inhibit the activities of catalase (CAT) and superoxide dismutase (SOD), increase the production of malondialdehyde (MDA) and reactive oxygen species (ROS), and cause uterine oxidative stress. Furthermore, ZEA affected the homeostasis of uterine cell proliferation and death by regulating the expression of proliferating cell nuclear antigen (PCNA) and activating the mitochondrial apoptotic pathway. ZEA-induced uterine injury might be related to the activation of p38/ERK MAPK signaling pathway. However, the regulatory effect of ZEA on the uterus was reversed after BA treatment. In conclusion, the uterus is an important target organ attacked by ZEA, and BA showed a good therapeutic effect.

The role of ER stress and ATP/AMPK in oxidative stress meditated hepatotoxicity induced by citrinin.

Citrinin, a secondary metabolite, can pose serious risks to the environment and organisms, but its hepatotoxic mechanisms are still unclear. Histopathological and ultrastructural results showed that citrinin-induced liver injury in Kunming mice, and the mechanism of citrinin-induced hepatotoxicity was studied in L02 cells. Firstly, citrinin mades L02 cell cycle arrest in G2/M phase by inhibition of cyclin B1, cyclin D1, cyclin-dependent kinases 2 (CDK2), and CDK4 expression. Secondly, citrinin inhibits proliferation and promotes apoptosis of L02 cells via disruption of mitochondria membrane potential, increase Bax/Bcl-2 ration, activation of caspase-3, 9, and enhance lactate dehydrogenase (LDH) release. Then, citrinin inhibits superoxide dismutase (SOD) activity and increases the accumulation of malondialdehyde (MDA) and reactive oxygen species (ROS), resulting oxidative damage in L02 cells; upregulates the protein expression of binding immunoglobulin protein (Bip), C/EBP homologous protein (CHOP), PKR-like ER kinase (PERK) and activating transcription factor6 (ATF6), inducing ER stress in L02 cells; increases the phosphorylation of AMP-activated protein kinase (AMPK) and decreases the content of adenosine-triphosphate (ATP), activating AMPK pathway in L02 cells. Eventually, pretreatment with NAC, an ROS inhibitor, alleviates citrinin-induced cell cycle G2/M arrest and apoptosis by inhibiting ROS-mediated ER stress; pretreatment with 4-PBA, an ER stress inhibitor, reversed ER stress and p-AMPK; pretreatment with dorsomorphin, an AMPK inhibitor, decreases citrinin-induced cell cycle G2/M arrest and apoptosis. In summary, citrinin induces cell cycle arrest and apoptosis to aggravate liver injury by activating ROS-ER stress-AMPK signaling pathway.