TSPA as a novel ATF6α translocation inducer efficiently ameliorates insulin sensitivity restoration and glucose homeostasis in db/db mice

Significance of Triazole in Medicinal Chemistry: Advancement in Drug Design, Reward and Biological Activity

One of the triazole tautomers, 1,2,4-triazole derivatives, has a wide range of biological activities that suggest its potential therapeutic utility in medicinal chemistry. These actions include anti-inflammatory, anti-cancer, anti-bacterial, anti-tuberculosis, and anti-diabetic effects. Using computational simulations and models, we investigate the structure-activity relationships of 1,2,4-triazoles, showing how various modifications to the triazole core yield a variety of clinical therapeutic benefits. The review highlights the anti-inflammatory effect of 1,2,4-triazoles in relation to their ability to disrupt significant inflammatory mediators and pathways. We present in-silico data that illuminate the triazoles' capacity to inhibit cell division, encourage apoptosis, and stop metastasis in a range of cancer models. This review looks at the bactericidal and bacteriostatic properties of 1,2,4-triazole derivatives, with a focus on their potential efficacy against multi-drug resistant bacterial infections and their usage in tuberculosis therapy. In order to better understand these substances' potential anti-diabetic benefits, this review also looks at how they affect glucose metabolism regulation and insulin responsiveness. Coordinated efforts are required to translate the efficacy of 1,2,4-triazole compounds in preclinical models into practical therapeutic benefits. Based on the information provided, it can be concluded that 1,2,4-triazole derivatives are a promising class of diverse therapeutic agents with potential utility in a range of disorders. Their development and improvement might herald a new era of medical care that will be immensely advantageous to both patients and the medical community as a whole. This comprehensive research, which is further reinforced by in-silico investigations, highlights the great medicinal potential of 1,2,4-triazoles. Additionally, this study encourages more research into these substances and their enhancement for use in pharmaceutical development.

Salubrinal promotes phospho-eIF2α-dependent activation of UPR leading to autophagy-mediated attenuation of iron-induced insulin resistance

Identification of new mechanisms mediating insulin sensitivity is important to allow validation of corresponding therapeutic targets. In this study, we first used a cellular model of skeletal muscle cell iron overload and found that endoplasmic reticulum (ER) stress and insulin resistance occurred after iron treatment. Insulin sensitivity was assessed using cells engineered to express an Akt biosensor, based on nuclear FoxO localization, as well as western blotting for insulin signaling proteins. Use of salubrinal to elevate eIF2α phosphorylation and promote the unfolded protein response (UPR) attenuated iron-induced insulin resistance. Salubrinal induced autophagy flux and its beneficial effects on insulin sensitivity were not observed in autophagy-deficient cells generated by overexpressing a dominant-negative ATG5 mutant or via knockout of ATG7. This indicated the beneficial effect of salubrinal-induced UPR activation was autophagy-dependent. We translated these observations to an animal model of systemic iron overload-induced skeletal muscle insulin resistance where administration of salubrinal as pretreatment promoted eIF2α phosphorylation, enhanced autophagic flux in skeletal muscle and improved insulin responsiveness. Together, our results show that salubrinal elicited an eIF2α-autophagy axis leading to improved skeletal muscle insulin sensitivity both in vitro and in mice.

Differential unfolded protein response in skeletal muscle from non-diabetic glucose tolerant or intolerant patients with obesity before and after bariatric surgery

AIMS

Not all people with obesity become glucose intolerant, suggesting differential activation of cellular pathways. The unfolded protein response (UPR) may contribute to the development of insulin resistance in several organs, but its role in skeletal muscle remains debated. Therefore, we explored the UPR activation in muscle from non-diabetic glucose tolerant or intolerant patients with obesity and the impact of bariatric procedures.

METHODS

Muscle biopsies from 22 normoglycemic (NG, blood glucose measured 120 min after an oral glucose tolerance test, G120 < 7.8 mM) and 22 glucose intolerant (GI, G120 between 7.8 and 11.1 mM) patients with obesity were used to measure UPR activation by RTqPCR and western blot. Then, UPR was studied in biopsies from 7 NG and 7 GI patients before and 1 year after bariatric surgery.

RESULTS

Binding immunoglobulin protein (BIP) protein was ~ 40% higher in the GI compared to NG subjects. Contrastingly, expression of the UPR-related genes BIP, activating transcription factor 6 (ATF6) and unspliced X-box binding protein 1 (XBP1u) were significantly lower and C/EBP homologous protein (CHOP) tended to decrease (p = 0.08) in GI individuals. While BIP protein positively correlated with fasting blood glucose (r = 0.38, p = 0.01), ATF6 and CHOP were associated with G120 (r = - 0.38 and r = - 0.41, p < 0.05) and the Matsuda index (r = 0.37 and r = 0.38, p < 0.05). Bariatric surgery improved metabolic parameters, associated with higher CHOP expression in GI patients, while ATF6 tended to increase (p = 0.08).

CONCLUSIONS

CHOP and ATF6 expression decreased in non-diabetic GI patients with obesity and was modified by bariatric surgery. These genes may contribute to glucose homeostasis in human skeletal muscle.

Endoplasmic Reticulum Stress in Metabolic Disorders

Metabolic disorders have become among the most serious threats to human health, leading to severe chronic diseases such as obesity, type 2 diabetes, and non-alcoholic fatty liver disease, as well as cardiovascular diseases. Interestingly, despite the fact that each of these diseases has different physiological and clinical symptoms, they appear to share certain pathological traits such as intracellular stress and inflammation induced by metabolic disturbance stemmed from over nutrition frequently aggravated by a modern, sedentary life style. These modern ways of living inundate cells and organs with saturating levels of sugar and fat, leading to glycotoxicity and lipotoxicity that induce intracellular stress signaling ranging from oxidative to ER stress response to cope with the metabolic insults (Mukherjee, et al., 2015). In this review, we discuss the roles played by cellular stress and its responses in shaping metabolic disorders. We have summarized here current mechanistic insights explaining the pathogenesis of these disorders. These are followed by a discussion of the latest therapies targeting the stress response pathways.