The Global Epidemiology of Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis Among Patients With Type 2 Diabetes.

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD), now known as metabolic dysfunction associated steatotic liver disease (MASLD), is closely associated with type 2 diabetes (T2D). Our aim was to estimate the most recent global prevalence of NAFLD/MASLD, nonalcoholic steatohepatitis (NASH), now known as metabolic dysfunction associated steatohepatitis (MASH), advanced fibrosis, and mortality among patients with T2D. METHODS: We systematically searched PubMed and Ovid MEDLINE for terms including NAFLD, NASH, and T2D published in 1990-2023 according to PRISMA. The meta-analysis was conducted using a random-effects model. Assessment of bias risk used the Joanna Briggs Institute appraisal tool. RESULTS: From 3134 studies included in the initial search, 123 studies (N = 2,224,144 patients with T2D) were eligible. Another 12 studies (N = 2733 T2D patients with liver biopsy) were eligible for histologic assessments. The global pooled prevalence of NAFLD/MASLD among patients with T2D was 65.33% (95% confidence interval, 62.35%-68.18%). This prevalence increased from 55.86% (42.38%-68.53%) in 1990-2004 to 68.81% (63.41%-73.74%) in 2016-2021 (P = .073). The highest NAFLD/MASLD prevalence among T2D patients was observed in Eastern Europe (80.62%, 75.72%-84.73%), followed by the Middle East (71.24%, 62.22%-78.84%), and was lowest in Africa (53.10%, 26.05%-78.44%). Among patients with liver biopsy data, the global pooled prevalence of NASH/MASH, significant fibrosis, and advanced fibrosis was 66.44% (56.61%-75.02%), 40.78% (24.24%-59.70%), and 15.49% (6.99%-30.99%), respectively. The pooled all-cause mortality was 16.79 per 1000 person-years (PY) (10.64-26.40), 4.19 per 1000 PY (1.34-7.05) for cardiac-specific mortality; 6.10 per 1000 PY (0.78-4.88) for extrahepatic cancer-specific mortality; and 2.15 per 1000 PY (0.00-2.21) for liver-specific mortality. CONCLUSIONS: The prevalence of NAFLD/MASLD among T2D is high and growing. The majority of NAFLD/MASLD patients with T2D have NASH/MASH, and a significant proportion have advanced fibrosis.

Cellular senescence in aging: Molecular basis, implications and therapeutic interventions.

Cellular senescence is an irreversible proliferation arrest in response to cellular damage and stress. Although cellular senescence is a highly stable cell cycle arrest, it can influence many physiological, pathological, and aging processes. Cellular senescence can be triggered by various intrinsic and extrinsic stimuli such as oxidative stress, mitochondrial dysfunction, genotoxic stress, oncogenic activation, irradiation and chemotherapeutic agents. Senescence is associated with several molecular and phenotypic alterations, such as senescence-associated secretory phenotype (SASP), cell cycle arrest, DNA damage response (DDR), senescence-associated ß-galactosidase, morphogenesis, and chromatin remodeling. Cellular senescence is a regular physiological event involved in tissue homeostasis, embryonic development, tissue remodeling, wound healing, and inhibition of tumor progression. Mitochondria are one of the organelles that undergo significant morphological and metabolic changes associated with senescence. Recent evidence unraveled that inter-organelle communication regulates cellular senescence, where mitochondria form a highly complex and dynamic network throughout the cytoplasm with other organelles, like the endoplasmic reticulum. An imbalance in organelle interactions may result in faulty cellular homeostasis, which contributes to cellular senescence and is associated with organ aging. Since mitochondrial dysfunction is a common characteristic of cellular senescence and age-related diseases, mitochondria-targeted senolytic or redox modulator senomorphic strategies help solve the complex problems with the detrimental consequences of cellular senescence. Understanding the regulation of mitochondrial metabolism would provide knowledge on effective therapeutic interventions for aging and age-related pathologies. This chapter focuses on the biochemical and molecular mechanisms of senescence and targeting senescence as a potential strategy to alleviate age-related pathologies and support healthy aging.

Loss of tRNA methyltransferase 9 and DNA damage response genes in yeast confers sensitivity to aminoglycosides.

tRNA methyltransferase 9 (Trm9)-catalysed tRNA modifications have been shown to translationally enhance the DNA damage response (DDR). Here, we show that Saccharomyces cerevisiae trm9Δ, distinct DNA repair and spindle assembly checkpoint (SAC) mutants are differentially sensitive to the aminoglycosides tobramycin, gentamicin and amikacin, indicating DDR and SAC activation might rely on translation fidelity, under aminoglycoside stress. Further, we report that the DNA damage induced by aminoglycosides in the base excision repair mutants ogg1Δ and apn1Δ is mediated by reactive oxygen species, which induce the DNA adduct 8-hydroxy deoxyguanosine. Finally, the synergistic effect of tobramycin and the DNA-damaging agent bleomycin to sensitize trm9Δ and the DDR mutants mlh1Δ, rad51Δ, mre11Δ and sgs1Δ at significantly lower concentrations compared with wild-type suggests that cells with tRNA modification dysregulation and DNA repair gene defects can be selectively sensitized using a combination of translation inhibitors and DNA-damaging agents.

Insulin Enhances Endothelial Function Throughout the Arterial Tree in Healthy But Not Metabolic Syndrome Subjects.

CONTEXT: Insulin reportedly impairs endothelial function in conduit arteries but improves it in resistance and microvascular arterioles in healthy humans. No studies have assessed endothelial function at three arterial levels in healthy or metabolic syndrome (METSYN) subjects. OBJECTIVE: The objective of the study was to compare endothelial responsiveness of conduit arteries, resistance, and microvascular arterioles to insulin in healthy and METSYN subjects. DESIGN: We assessed conduit, resistance, and microvascular arterial function in the postabsorptive and postprandial states and during euglycemic hyperinsulinemia (insulin clamp). SETTING: The study was conducted at a clinical research unit. PARTICIPANTS: Age-matched healthy and METSYN subjects participated in the study. INTERVENTIONS: We used brachial flow-mediated dilation, forearm postischemic flow velocity, and contrast-enhanced ultrasound to assess the conduit artery, resistance arteriole, and microvascular arteriolar endothelial function, respectively. We also assessed the conduit artery stiffness (pulse wave velocity and augmentation index) and measured the plasma concentrations of 92 cardiovascular disease biomarkers at baseline and after the clamp. RESULTS: Postabsorptive and postprandial endothelial function was similar in controls and METSYN in all tested vessels. METSYN subjects were metabolically insulin resistant (P < .005). In controls, but not METSYN subjects, during euglycemic hyperinsulinemia, endothelial function improved at each level of arterial vasculature (P < .05 or less for each). Conduit vessel stiffness (pulse wave velocity) was increased in the METSYN group. Twelve of 92 biomarkers differed at baseline (P < .001) and remained different at the end of the insulin clamp. CONCLUSIONS: We conclude that insulin enhances arterial endothelial function in health but not in METSYN, and this vascular insulin resistance may underlie its increased cardiovascular disease risk.

Hyaluronic Acid as an adjunct to scaling and root planing in chronic periodontitis. A randomized clinical trail.

AIM: AIM of the present study was to evaluate the adjunctive effect of local application of hyaluronon gel following scaling and root planing (SRP) in chronic periodontitis patients. MATERIALS AND METHODS: In this randomized split mouth study 33 subjects with chronic periodontitis were evaluated after full mouth SRP. In the test sites hyaluronon gel was applied immediately after SRP and one week post therapy, the control sites were treated with SRP alone. Bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL) were recorded at baseline, 4 wk and 12 wk. RESULTS: Significant reduction in BOP scores was observed in both the groups at 12weeks (p<0.001). The hyaluronon group showed a greater reduction in BOP (p<0.001). In the hyaluronon group the mean PPD at baseline was 6.33±0.09 which reduced to 2.49±0.51 at 12 weeks which was statistically significant (p<0.001). In the control group the mean PPD at baseline was 6.09±1.26 which reduced to 4.36±1.29 at 12 weeks which was statistically significant (p<0.001). The CAL measurements showed a significant difference between the groups (p<0.001) at 12 wk post therapy. CONCLUSION: Hyaluronic Acid (HA) has a beneficial effect on periodontal health in patients with chronic Periodontitis. HA appears to be a suitable candidate as an adjunct to SRP in chronic periodontitis patients.

An unusual case of hypercalcemia associated with graves' disease and vitamin d deficiency.

OBJECTIVE: To present a case of hypercalcemia associated with thyrotoxicosis in a patient with vitamin D deficiency and review biochemical changes during the course of treatment. METHODS: We report a case, describe the changes in serum calcium, phosphorus, parathyroid hormone in Graves' disease and concomitant Vitamin D deficiency. We compare our findings to those reported in literature. RESULTS: Our patient had hypercalcemia secondary to thyrotoxicosis alone, which was confirmed by low parathyroid hormone level and resolution of hypercalcemia with treatment of thyrotoxicosis. The case was complicated by a concomitant vitamin D deficiency. Serum calcium elevation in patients with thyrotoxicosis occurs secondary to hyperthyroidism alone or due to concurrent hyperparathyroidism. Hypercalcemia from thyrotoxicosis is usually asymptomatic and is related to bone resorption. Vitamin D deficiency can be seen in patients with thyrotoxicosis because of accelerated metabolism, poor intestinal absorption and increased demand during bone restoration phase. Coexistence of hypercalcemia and Vitamin D deficiency in patients with thyrotoxicosis is rare, but possible, and 25-hydroxyvitamin D levels should be checked. The definite treatment for hypercalcemia in thyrotoxicosis is correction of thyroid function. CONCLUSION: Hypercalcemia in thyrotoxicosis should be distinguished from concomitant hyperparathyroidism and confirmed by resolution of hypercalcemia with control of thyrotoxicosis. Patients with hypercalcemia and thyrotoxicosis may also have vitamin D deficiency and 25-OH Vitamin D levels should be checked.

Distinct regulatory role for RFL, the rice LFY homolog, in determining flowering time and plant architecture.

Activity of axillary meristems dictates the architecture of both vegetative and reproductive parts of a plant. In Arabidopsis thaliana, a model eudicot species, the transcription factor LFY confers a floral fate to new meristems arising from the periphery of the reproductive shoot apex. Diverse orthologous LFY genes regulate vegetative-to-reproductive phase transition when expressed in Arabidopsis, a property not shared by RFL, the homolog in the agronomically important grass, rice. We have characterized RFL by knockdown of its expression and by its ectopic overexpression in transgenic rice. We find that reduction in RFL expression causes a dramatic delay in transition to flowering, with the extreme phenotype being no flowering. Conversely, RFL overexpression triggers precocious flowering. In these transgenics, the expression levels of known flowering time genes reveal RFL as a regulator of OsSOC1 (OsMADS50), an activator of flowering. Aside from facilitating a transition of the main growth axis to an inflorescence meristem, RFL expression status affects vegetative axillary meristems and therefore regulates tillering. The unique spatially and temporally regulated RFL expression during the development of vegetative axillary bud (tiller) primordia and inflorescence branch primordia is therefore required to produce tillers and panicle branches, respectively. Our data provide mechanistic insights into a unique role for RFL in determining the typical rice plant architecture by regulating distinct downstream pathways. These results offer a means to alter rice flowering time and plant architecture by manipulating RFL-mediated pathways.

The making of a bushy grass with a branched flowering stem: Key rice plant architecture traits regulated by RFL the rice LFY homolog.

In Arabidopsis thaliana, a eudicot species, the transcription factor LFY is expressed throughout the floral meristem and promotes their formation. The expression pattern of the rice LFY homolog-RFL shows distinct differences from that of its Arabidopsis counterpart. In the March issue of PNAS (2008) we have shown the temporally-regulated high-level expression of RFL in the apical meristem is necessary for its transition to an inflorescence meristem and thus to initiate flowering. RFL controls the time taken for flowering, by activating integrators of flowering signals such as OsSOC1 and RFT1. Further, the dynamic pattern of RFL expression in the branching inflorescence meristem (panicle) and in vegetative axillary meristems (tiller buds) is required for panicle branching and tiller outgrowth. Thus RFL functions determine the architecture of the rice plant. Here we propose a plausible model for a regulatory feedback loop between RFL and OsSOC1/RFT1 in controlling the vegetative to flowering phase transition. We discuss the possibility that non-cell autonomous RFL functions may also regulate signaling the net outcome of which determines the rice plant body plan.