Dual Role of Caspase 8 in Adipocyte Apoptosis and Metabolic Inflammation.

Caspases are cysteine-aspartic proteases that were initially discovered to play a role in apoptosis. However, caspase 8, in particular, also has additional nonapoptotic roles, such as in inflammation. Adipocyte cell death and inflammation are hypothesized to be initiating pathogenic factors in type 2 diabetes. Here, we examined the pleiotropic role of caspase 8 in adipocytes and obesity-associated insulin resistance. Caspase 8 expression was increased in adipocytes from mice and humans with obesity and insulin resistance. Treatment of 3T3-L1 adipocytes with caspase 8 inhibitor Z-IETD-FMK decreased both death receptor-mediated signaling and targets of nuclear factor κ-light-chain-enhancer of activated B (NF-κB) signaling. We generated novel adipose tissue and adipocyte-specific caspase 8 knockout mice (aP2Casp8-/- and adipoqCasp8-/-). Both males and females had improved glucose tolerance in the setting of high-fat diet (HFD) feeding. Knockout mice also gained less weight on HFD, with decreased adiposity, adipocyte size, and hepatic steatosis. These mice had decreased adipose tissue inflammation and decreased activation of canonical and noncanonical NF-κB signaling. Furthermore, they demonstrated increased energy expenditure, core body temperature, and UCP1 expression. Adipocyte-specific activation of Ikbkb or housing mice at thermoneutrality attenuated improvements in glucose tolerance. These data demonstrate an important role for caspase 8 in mediating adipocyte cell death and inflammation to regulate glucose and energy homeostasis. ARTICLE HIGHLIGHTS: Caspase 8 is increased in adipocytes from mice and humans with obesity and insulin resistance. Knockdown of caspase 8 in adipocytes protects mice from glucose intolerance and weight gain on a high-fat diet. Knockdown of caspase 8 decreases Fas signaling, as well as canonical and noncanonical nuclear factor κ-light-chain-enhancer of activated B (NF-κB) signaling in adipose tissue. Improved glucose tolerance occurs via reduced activation of NF-κB signaling and via induction of UCP1 in adipocytes.

Disruption of adipocyte YAP improves glucose homeostasis in mice and decreases adipose tissue fibrosis.

OBJECTIVE: Adipose tissue is a very dynamic metabolic organ that plays an essential role in regulating whole-body glucose homeostasis. Dysfunctional adipose tissue hypertrophy with obesity is associated with fibrosis and type 2 diabetes. Yes-associated protein 1 (YAP) is a transcription cofactor important in the Hippo signaling pathway. However, the role of YAP in adipose tissue and glucose homeostasis is unknown. METHODS: To study the role of YAP with metabolic stress, we assessed how increased weight and insulin resistance impact YAP in humans and mouse models. To further investigate the in vivo role of YAP specifically in adipose tissue and glucose homeostasis, we developed adipose tissue-specific YAP knockout mice and placed them on either chow or high fat diet (HFD) for 12-14 weeks. To further study the direct role of YAP in adipocytes we used 3T3-L1 cells. RESULTS: We found that YAP protein levels increase in adipose tissue from humans with type 2 diabetes and mouse models of diet-induced obesity and insulin resistance. This suggests that YAP signaling may contribute to adipocyte dysfunction and insulin resistance under metabolic stress conditions. On an HFD, adipose tissue YAP knockout mice had improved glucose tolerance compared to littermate controls. Perigonadal fat pad weight was also decreased in knockout animals, with smaller adipocyte size. Adipose tissue fibrosis and gene expression associated with fibrosis was decreased in vivo and in vitro in 3T3-L1 cells treated with a YAP inhibitor or siRNA. CONCLUSIONS: We show that YAP is increased in adipose tissue with weight gain and insulin resistance. Disruption of YAP in adipocytes prevents glucose intolerance and adipose tissue fibrosis, suggesting that YAP plays an important role in regulating adipose tissue and glucose homeostasis with metabolic stress.

Sand Particle Size and Phosphorus Amount Affect Rhizophagus irregularis Spore Production Using In Vitro Propagated Spore as a Starter Inoculum in Rhizosphere of Maize (Zea mays) Plantlets.

Microbial inoculants, particularly arbuscular mycorrhizal (AM) fungi, have great potential for sustainable crop management. In this study, monoxenic culture of indigenous R. irregularis was developed and used as a tool to determine the minimum phosphorus (P) level for maximum spore production under the in vitro conditions. This type of starter AM fungal inoculum was then applied to an in vivo substrate-based mass-cultivation system. Spore production, colonization rate, and plant growth were examined in maize (Zea mays L.) plant inoculated with the monoxenic culture of R. irregularis in sand graded by particle size with varying P levels in nutrient treatments. In the in vitro culture, the growth medium supplemented with 20 µM P generated the maximum number of spores (400 spores/mL media) of R. irregularis. In the in vivo system, the highest sporulation (≈500 spores g-1 sand) occurred when we added a half-strength Hoagland solution (20 µM P) in the sand with particle size between 500 µm and 710 µm and omitted P after seven weeks. However, the highest colonization occurred when we added a half-strength Hoagland solution in the sand with particle sizes between 710 µm and 1000 µm and omitted P after seven weeks. This study suggests that substrate particle size and P reduction and regulation might have a strong influence on the maximization of sporulation and colonization of R. irregularis in sand substrate-based culture.

A secondary approach with conventional medicines and supplements to recuperate current COVID-19 status.

Novel coronavirus 2019 (COVID-19) is a zoonosis that revised the global economic and societal progress since early 2020. The SARS-CoV-2 has been recognized as the responsible pathogen for COVID-19 with high infection and mortality rate potential. It has spread in 192 countries and infected about 1.5% of the world population, and still, a proper therapeutic approach is not unveiled. COVID-19 indication starts with fever to shortness of breathing, leading to ICU admission with the ventilation support in severe conditions. Besides the symptomatic mainstay clinical therapeutic approach, only Remdesivir has been approved by the FDA. Several pharmaceutical companies claimed different vaccines with exceptionally high efficacy (90-95%) against COVID-19; how long these vaccines can protect and long-term safety with the new variants are unpredictable. After the worldwide spread of the COVID-19 pandemic, numerous clinical trials with different phases are being performed to find the most appropriate solution to this condition. Some of these trials with old FDA-approved drugs showed promising results. In this review, we have precisely compiled the efforts to curb the disease and discussed the clinical findings of Ivermectin, Doxycycline, Vitamin-D, Vitamin-C, Zinc, and cannabidiol and their combinations. Additionally, the correlation of these molecules on the prophylactic and diseased ministration against COVID-19 has been explored.

Neferine improves oxidative stress and apoptosis in benign prostate hyperplasia via Nrf2-ARE pathway.

BACKGROUND: Progression of Benign Prostate hyperplasia (BPH) is vulnerable to oxidative stress (OS) and prostatic enlargement among the aging males through apoptosis deregulation. Our present study aimed to investigate the effect of neferine (NF) in the regulation of oxidative stress and apoptosis in human BPH-1 cells. METHODS: BPH epithelial cell line BPH-1 was treated with NF for 24 and 48 h. To measure oxidative stress (OS) we investigated MDA, SOD, and GST expression along with Nrf2 and its downstream gene and protein expression. Cell proliferation and apoptosis regulation was assayed with respective methods. RESULTS: Investigation revealed NF remarkably activate Nrf2 and its downstream proteins HO-1 and NQO1 at 48 h more substantially. Nrf2/Keap1 relative gene and protein expression indicated that NF might trigger Nrf2 upregulation by decreasing Keap1 expression. Both NF concentrations (3 µM and 9 µM) were able to deplete ROS and lipid peroxidation, concurrently, up-regulated SOD and GST. NF reduced cell proliferation significantly along with the regulation of apoptotic proteins Bax, Bcl2, Cyt-C, Caspase 9, and Caspase 3 at the same time (48 h). CONCLUSION: This study is the first to manifest that NF may potentially regulate BPH by counterbalancing between OS and apoptosis through the activation of Nrf2-ARE pathway.

Signaling pathways and proteins targeted by antidiabetic chalcones.

Chalcones have shown a broad spectrum of biological activities with clinical potential against various diseases. The biological activities are mainly attributed to the presence of α, ß-unsaturated carbonyl system, perceived as potential Michael acceptors. In this review, we discussed the antioxidant potential of chalcones and elucidated the mechanisms of pathways and proteins such as carbohydrate digestive enzymes (α-amylase and α-glucosidase), aldose reductase, SGLT-2, and Nrf2 that are targeted by antidiabetic chalcones. In addition to their insulin mimetic potential, we explore the major molecular targets of chalcones and discuss the biochemical and therapeutic implication of modulating these targets. Finally, we dwell on the opulence of the literature and envisage how RNA interference-mediated gene silencing technique and in silico molecular docking could be exploited in the search for novel and more efficacious antidiabetic chalcones.

Current etiological comprehension and therapeutic targets of acetaminophen-induced hepatotoxicity.

Acetaminophen (APAP) is the most popular mild analgesic and antipyretic drug used worldwide. APAP overdose leads to drug-induced hepatotoxicity and can cause hepatic failure if treatment delayed. It is adequately comprehended that the metabolism of high-dose APAP by cytochrome P450 enzymes generates N-acetyl-p-benzoquinone imine (NAPQI), a toxic metabolite, which leads to glutathione (GSH) depletion, oxidative stress, and activation of various complex molecular pathways that initiate liver injury and downstream hepatic necrosis. Administration of activated charcoal followed by N-acetylcysteine (NAC) is considered the mainstay therapy; however, including side effects and limitation of rescuing for the delayed patients where liver transplantation may be a lifesaving procedure. Many complex signal transduction pathways such as c-Jun NH2-terminal kinase (JNK), mammalian target of rapamycin (mTOR), nuclear factor (NF)-κB, and NF (erythroid-derived 2)- like 2 (Nrf2) are involved in the development of APAP hepatotoxicity, but yet hasn't been comprehensively studied; thus, the search for effective antidotes and better management strategies continues. Here, we reviewed the most current advances to elucidate the etiological factors and therapeutic targets that could provide better strategies for the management of APAP-induced hepatotoxicity.

One month of the novel coronavirus 2019 outbreak: Is it still a threat?

The novel coronavirus 2019 disease (COVID-19) is now in an outbreak not only in China but also around the world, suspected to be originated from a wet market in Wuhan, Hubei province, China. The flare-up of COVID-19, it has already been infected 78,811 people with 2462 fatalities in 1 month window. The most alarming issue is the virus can transmit from host to host and still asymptomatic. Currently, 24 counties with 505 confirmed cases have been reported. Presently, there is no specific treatment or vaccine but physicians are battling with the use of antibiotics, steroid, anti-viral and anti-HIV drugs and some of the infected cases are testified improved. WHO and China National health Commission are cooperatively striving to come up with elucidation but it will take a minimum of 3 to 4 months at least to undergo a phase-1 trial. However, the soaring rates of spreading each day has become much stable which might even improve within the next few weeks in China but not for some other countries. Healthy peoples are instructed to avoid public gathering, always wearing the mask and frequently wash hands. Currently, China has able to hold up more than 97.7% infection within China but a scientific breakthrough is crucial before it's too late.

Microsomal prostaglandin E synthase 2 deficiency is resistant to acetaminophen-induced liver injury.

Acetaminophen (APAP)-induced liver injury is the main cause of acute liver failure. This study investigated the role of microsomal prostaglandin E synthase 2 (mPGES-2), discovered as one of the prostaglandin E2 (PGE2) synthases, in mediating APAP-induced liver injury. Using mPGES-2 wild-type (WT) and knockout (KO) mice, marked resistance to APAP-induced liver damage was found in mPGES-2 KO, as indicated by robust improvement of liver histology, changes in liver enzyme release, and marked decrease in APAP-cysteine adducts (APAP-CYS) and inflammatory markers. Moreover, the results confirmed that increase in liver PGE2 content in KO mice under basal conditions was not critical for the protection from APAP-induced liver injury. Importantly, mPGES-2 deletion inhibited the production of malondialdehyde (MDA), increasing glutathione (GSH) level. Enhanced GSH level may contribute to the inhibition of APAP toxicity in mPGES-2 KO mice. To further elucidate the role of mPGES-2 in the liver injury induced by APAP, adeno-associated viruses (AAV) were used to overexpress mPGES-2 in the liver. The results showed that mPGES-2 overexpression aggravates liver injury associated with an increase in inflammatory markers and chemokines after APAP treatment. Moreover, a lower level of GSH was detected in the mPGES-2 overexpression group compared to the control group. Collectively, our findings indicate that mPGES-2 plays a critical role in regulating APAP-induced liver injury, possibly by regulating GSH and APAP-CYS level, which may provide a potential therapeutic strategy for the prevention and treatment of APAP-induced liver injury.

Mangiferin ameliorates acetaminophen-induced hepatotoxicity through APAP-Cys and JNK modulation.

An overdose of the most popular analgesic, acetaminophen (APAP), is one of the leading causes of acute liver failure. It is well established that glutathione is exhausted by APAP-reactive intermediate N­acetyl­p­benzoquinone-imine (NAPQI). This leads to elevated phosphorylated-c-Jun N-terminal kinase (p-JNK), which further activates reactive oxygen species (ROS), initiates an inflammatory response, and finally leads to severe hepatic injury. The present study was conducted to investigate the protective role of mangiferin (MAN), a naturally occurring xanthone and anti-oxidant, on APAP-induced hepatotoxicity. C57BL/6 mice were pretreated with or without MAN at 1 h prior to APAP challenge. MAN was administered at a dose of 12.5-50 mg/kg along with APAP at a dose of 400 mg/kg. According to the ALT/AST ratio, 25 mg/kg MAN was the most potent dose for further experiments. Serum ALT and AST depletion were observed in APAP + MAN (25 mg/kg)-treated mice at 6, 12, and 24 h. Early (1 h after APAP treatment) GSH depletion by APAP overdose was restored by MAN treatment, which reduced APAP-Cys adduct formation and promoted protection. p-JNK downregulation and AMPK activation were observed in MAN-treated mice, which could mechanistically reduce oxidative stress and inflammation. MAN up-regulated liver GSH and SOD and reduced lipid peroxidation. HO-1 protein and p47 phox mRNA expression indicated that MAN regulated oxidative stress along with JNK deactivation. The expression of inflammatory response genes TNF-α, IL-6, MCP-1, CXCL-1, and CXCL-2 reached the basal levels after MAN treatment. mRNA, protein, and serum levels of IL-1ß were reduced, and NF-κB expression was similar to that of the MAN-treated APAP mice. MAN post-treatment (1 h after APAP treatment) also protected the mice from hepatotoxicity. In conclusion, MAN had a protective and therapeutic role in APAP-induced hepatotoxicity by improving the metabolism of acetaminophen and APAP-Cys adduct formation followed by JNK-mediated oxidative stress and inflammation.