Empagliflozin Attenuates Hyperuricemia by Upregulation of ABCG2 via AMPK/AKT/CREB Signaling Pathway in Type 2 Diabetic Mice

A minireview: Role of AMP-activated protein kinase (AMPK) signaling in obesity-related renal injury

Emerging evidence shows that the AMP-activated protein kinase (AMPK), a critical energy-sensing switch, plays an important role in the pathogenesis and development of obesity-related renal injury. In this review, we summarized the mechanisms underlying the protective effects of AMPK activation against obesity-related renal injury in preclinical studies, with the main purposes of increasing the understanding of AMPK and providing new insights into the future clinical therapeutic strategies. The renoprotective effects of AMPK mainly act by modulating lipid metabolism and autophagy and suppressing oxidative stress, inflammation, and fibrosis. More importantly, we discussed the recent advances in this field that require further investigation. Firstly, the inhibitory effect of AMPK on ferroptosis is a potential mechanism for its protection against renal injury. Secondly, the effect of AMPK on lipolysis is complex: AMPK induces basal lipolysis but also inhibits stimulated lipolysis. Thirdly, statins may play a renoprotective role by activating AMPK. Fourthly, some microRNAs targeting AMPK mRNA have been implicated in diabetic nephropathy in type 2 diabetes. Further, AMPK can regulate the expression of some microRNAs, suggesting that the stable renoprotective effects of AMPK may benefit from its epigenetic regulation. Lastly, several natural compounds and synthetic drugs have been recognized to protect against obesity-related renal injury by activating AMPK and its downstream pathways in animal models. It remains to be seen if combination of newly identified drugs with traditional renoprotective medicine will have any synergistic therapeutic benefits without adding to side effects.

An SGLT2 inhibitor modulates SHH expression by activating AMPK to inhibit the migration and induce the apoptosis of cervical carcinoma cells

In addition to their hypoglycemic effect, sodium-glucose cotransporter 2 (SGLT2) inhibitors have many other benefits. In the present study, we examine the anticancer effect of the SGLT2 inhibitor empagliflozin using cervical carcinoma models. In vivo antitumor activities of empagliflozin were observed in a nude mouse model. Empagliflozin intervention and downregulation of Sonic Hedgehog Signaling Molecule (Shh) inhibited the migration and promoted the apoptosis of cervical cancer cells in nude mice. Compared with the control group, the empagliflozin treatment group had an increased level of AMP-activated protein kinase (AMPK) and decreased levels of Forkhead Box A1 (FOXA1) and SHH in tumor tissue. In vitro experiments also showed that empagliflozin (50 μM) inhibited the migration of cervical cancer cells and induced their apoptosis by activating the AMPK/FOXA1 pathway and inhibiting the expression of SHH. Kaplan-Meier survival analysis was used to determine the relationship between SHH expression and total survival time. The results showed that in cervical cancer patients, high SHH expression resulted in unfavorable overall survival. The downregulation of SHH with small interfering RNA (siRNA) inhibited the migration and invasion and promoted the apoptosis of HeLa cells. These findings show that empagliflozin has a potential therapeutic effect on cervical cancer. This effect was related to the activation of the AMPK pathway and the inhibition of SHH expression.

Cardioprotective Effects of Sirtuin-1 and Its Downstream Effectors: Potential Role in Mediating the Heart Failure Benefits of SGLT2 (Sodium-Glucose Cotransporter 2) Inhibitors

The cardioprotective effects of SGLT2 (sodium-glucose cotransporter 2) inhibitors may be related to their ability to induce a fasting-like paradigm, which triggers the activation of nutrient deprivation pathways to promote cellular homeostasis. The most distinctive metabolic manifestations of this fasting mimicry are enhanced gluconeogenesis and ketogenesis, which are not seen with other antihyperglycemic drugs. The principal molecular stimulus to gluconeogenesis and ketogenesis is activation of SIRT1 (sirtuin-1) and its downstream mediators: PGC-1α (proliferator-activated receptor gamma coactivator 1-alpha) and FGF21 (fibroblast growth factor 21). These three nutrient deprivation sensors exert striking cardioprotective effects in a broad range of experimental models. This benefit appears to be related to their actions to alleviate oxidative stress and promote autophagy-a lysosome-dependent degradative pathway that disposes of dysfunctional organelles that are major sources of cellular injury. Nutrient deprivation sensors are suppressed in states of perceived energy surplus (ie, type 2 diabetes mellitus and chronic heart failure), but SGLT2 inhibitors activate SIRT1/PGC-1α/FGF21 signaling and promote autophagy. This effect may be related to their action to trigger the perception of a system-wide decrease in environmental nutrients, but SGLT2 inhibitors may also upregulate SIRT1, PGC-1α, and FGF21 by a direct effect on the heart. Interestingly, metformin-induced stimulation of AMP-activated protein kinase (a nutrient deprivation sensor that does not promote ketogenesis) has not been shown to reduce heart failure events in clinical trials. Therefore, promotion of ketogenic nutrient deprivation signaling by SGLT2 inhibitors may explain their cardioprotective effects, even though SGLT2 is not expressed in the heart.

Renal disorders in rheumatologic diseases: the spectrum is changing (part 2. Arthridides)

This review is devoted to rheumatologic diseases mainly characterized by different types of arthritis. They may involve also different organs, including the kidney, but renal disease is more frequently caused by the nephrotoxicity of drugs to relieve pain or to interfere with the pathophysiology of the underlying disease. Rheumatoid arthritis is the prototype of arthropathies. This autoimmune disease mainly attacks joints, tendons and ligaments but can also involve internal organs including the kidney. Psoriatic arthritis is a complex disease in which psoriasis, a chronic inflammatory disease, is associated with the development of peripheral arthritis or spondylitis. The disease or its treatment may lead to kidney complications. Gout is a form of inflammatory arthritis which is characterized by an increase in the serum uric acid deposits in and around the joints of the extremities, the so called tophi. The disease is often associated with a metabolic syndrome with diabetes, obesity, hypertension, and cardiovascular disease. Kidney injury is frequent. It may be caused by kidney stones, urinary tract obstruction, tubulointerstitial and vascular lesions leading to CKD and renal failure.