Reduced mitochondrial DNA content in lymphocytes is associated with insulin resistance and inflammation in patients with impaired fasting glucose

Relationship Between the Hemoglobin, Albumin, Lymphocyte Count, Platelet Count (HALP) Score and Type 2 Diabetes Retinopathy

Purpose

To explore the correlation between hemoglobin, albumin, lymphocyte count, platelet count (HALP) score and type 2 diabetic retinopathy (DR).

Methods

The study was conducted on 674 patients with type 2 diabetes (T2DM). According to the results of the fundus examination, they were divided into non-diabetic retinopathy group (NDR, n=388) and diabetic retinopathy group (DR, n=286). Collected patients baseline data, calculated HALP score, analyzed the correlation between HALP score and DR.

Results

In all patients, male patients and female patients, the HALP score of the DR group was lower than that of the NDR group (P<0.001), and the HALP score was negatively correlated with the incidence of DR (P<0.05). HALP score was independent risk factors for DR, regardless of gender. In male patients, HALP score and DR had a linear relationship, but in female patients, HALP score and DR showed a nonlinear relationship, and HALP score was more sensitive to the onset of DR in male patients. The combined diagnostic model of HALP score, course of disease, SBP and BUN was used to diagnose DR, and it was found that the diagnostic value was the highest among male patients, with AUC of 0.761, sensitivity of 58.3% and specificity of 80.3%.

Conclusion

HALP score was an independent risk factor for DR, attention should be paid to monitoring HALP score, especially in male T2DM patients. The accuracy of HALP score, disease course, SBP and BUN combined model diagnosis of DR was high, which can become a biological indicator for early screening of DR.

Mitochondrial DNA Copy Number and Risk of Diabetes Mellitus and Metabolic Syndrome

CONTEXT

Mitochondrial DNA (mtDNA) plays a key role in diabetes mellitus and metabolic syndrome (MetS). An increasing number of studies have reported the association between mtDNA copy number (mtDNA-CN) and the risk of diabetes mellitus and MetS; however, the associations remain conflicted and a systematic review and meta-analysis on the association between mtDNA-CN and diabetes mellitus and MetS is lacking.

OBJECTIVE

We aimed to investigate the association of mtDNA-CN and diabetes mellitus and MetS using a systematic review and meta-analysis of observational studies.

METHODS

PubMed, EMBASE, and Web of Science were searched up to December 15, 2022. Random-effect models were used to summarize the relative risks (RRs) and 95% CIs.

RESULTS

A total of 19 articles were included in the systematic review and 6 articles (12 studies) in the meta-analysis involving 21 714 patients with diabetes (318 870 participants) and 5031 MetS (15 040 participants). Compared to the highest mtDNA-CN, the summary RR (95% CIs) for the lowest mtDNA-CN were 1.06 (95% CI, 1.01-1.12; I2 = 79.4%; n = 8) for diabetes (prospective study: 1.11 (1.02-1.21); I2 = 22.6%; n = 4; case-control: 1.27 (0.66-2.43); I2 = 81.8%; n = 2; cross-sectional: 1.01 (0.99-1.03); I2 = 74.7%; n = 2), and 1.03 (0.99-1.07; I2 = 70.6%; n = 4) for MetS (prospective: 2.87 (1.51-5.48); I2 = 0; n = 2; cross-sectional: 1.02 (1.01-1.04); I2 = 0; n = 2).

CONCLUSION

Decreased mtDNA-CN was associated with increased risk of diabetes mellitus and MetS when limited to prospective studies. More longitudinal studies are warranted.

Celastrol attenuates high-fructose diet-induced inflammation and insulin resistance via inhibition of 11β-hydroxysteroid dehydrogenase type 1 activity in rat adipose tissues

High fructose consumption has been linked to low-grade inflammation and insulin resistance that results in increased intracellular 11ß-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity. Celastrol, a pentacyclic triterpene, has been demonstrated to exhibit multifaceted targets to attenuate various metabolic diseases associated with inflammation. However, the underlying mechanisms by which celastrol exerts its attributive properties on high fructose diet (HFrD)-induced metabolic syndrome remain elusive. Herein, the present study was aimed to elucidate the mechanistic targets of celastrol co-administrations upon HFrD in rats and evaluate its potential to modulate 11β-HSD1 activity. Celastrol remarkably improved glucose tolerance, lipid profiles, and insulin sensitivity along with suppression of hepatic glucose production. In rat adipose tissues, celastrol attenuated nuclear factor-kappa B (NF-κB)-driven inflammation, reduced c-Jun N-terminal kinases (JNK) phosphorylation, and mitigated oxidative stress via upregulated genes expression involved in mitochondrial biogenesis. Furthermore, insulin signaling pathways were significantly improved through the restoration of Akt phosphorylation levels at Ser473 and Thr308 residues. Celastrol exhibited a potent, selective and specific inhibitor of intracellular 11β-HSD1 towards oxidoreductase activity (IC₅₀ value = 4.3 nM) in comparison to other HSD-related enzymes. Inhibition of 11β-HSD1 expression in rat adipose microsomes reduced the availability of its cofactor NADPH and substrate H6PDH in couple to upregulated mRNA and protein expressions of glucocorticoid receptor. In conclusion, our results underscore the most likely conceivable mechanisms exhibited by celastrol against HFrD-induced metabolic dysregulations mainly through attenuating inflammation and insulin resistance, at least via specific inhibitions on 11β-HSD1 activity in adipose tissues.