Diabetes mellitus (DM) is known as one of important common endocrine disorders which could due to deregulation of a variety of cellular and molecular pathways. A large numbers studies indicated that ...various pathogenesis events including mutation, serin phosphorylation, and increasing/decreasing expression of many genes could contribute to initiation and progression of DM. Insulin resistance is one of important factors which could play critical roles in DM pathogenesis. It has been showed that insulin resistance via targeting a sequence of cellular and molecular pathways (eg, PI3 kinases, PPARγ co‐activator‐1, microRNAs, serine/threonine kinase Akt, and serin phosphorylation) could induce DM. Among of various factors involved in DM pathogenesis, microRNAs, and exosomes have been emerged as effective factors in initiation and progression of DM. A variety of studies indicated that deregulation of these molecules could change behavior of various types of cells and contribute to progression of DM. Resistin is other main factor which is known as signal molecule involved in insulin resistance. Multiple lines evidence indicated that resistin exerts its effects via affecting on glucose metabolism, inhibition of fatty acid uptake and metabolism with affecting on a variety of targets such as CD36, fatty acid transport protein 1, Acetyl‐CoA carboxylase, and AMP‐activated protein kinase. Here, we summarized various molecular aspects are associated with DM particularly the molecular pathways involved in insulin resistance and resistin in DM. Moreover, we highlighted exosomes and microRNAs as effective players in initiation and progression of DM.
DM is known as one of major metabolic disorders which are associated with a variety of Enviromental and gentical factors. Identification of cellular and molecular pathways involved in DM pathogenesis, could contribute to better understanding of disease condition and could provide new therapeutic approaches. Resistin is a hormone which plays critical roles in DM pathogenesis. Unlike the proven role of resistin in rodents, the main function of this hormone in relation to energy balance and IR in DM2 is not consistent in humans. Some surveys have reported enhanced RETN expression levels in DM2, IR, obesity, inflammation and metabolic syndrome, while some studies failed to identify any alteration in circulating resistin levels in aforementioned conditions. Further clinical studies are necessary to clarify the correlation between resistin levels and DM2. MicroRNAs and exosomes are other important molecules involved in DM pathogensis. These molecules could exert their effects via targeting a sequence of cellular and molecular pathways involved in different stages of DM pathogenesis. Hence, identification of these molecules cold lead to better drawing of cellular and molecular targets involved in DM. Moreover, numerous studies indicated that miRNAs and exosomes could be used as powerful diagnostic and therapeutic biomarkers in DM therapy.
Metabolic syndrome is known as a frequent precursor of type 2 diabetes mellitus (T2D). This disease could affect 8% of the people worldwide. Given that pancreatic β‐cell dysfunction and loss have ...central roles in the initiation and progression of the disease, the understanding of cellular and molecular pathways associated with pancreatic β‐cell dysfunction can provide more information about the underlying pathways involved in T2D. Multiple lines evidence indicated that oxidative stress, microRNA, and long noncoding RNA play significant roles in various steps of diseases. Oxidative stress is one of the important factors involved in T2D pathogenesis. This could affect the function and survival of the β cell via activation or inhibition of several processes and targets, such as receptor‐signal transduction, enzyme activity, gene expression, ion channel transport, and apoptosis. Besides oxidative stress, microRNAs and noncoding RNAs have emerged as epigenetic regulators that could affect pancreatic β‐cell dysfunction. These molecules exert their effects via targeting a variety of cellular and molecular pathways involved in T2D pathogenesis. Here, we summarized the molecular aspects of pancreatic β‐cell dysfunction. Moreover, we highlighted the roles of oxidative stress, microRNAs, and noncoding RNAs in pancreatic β‐cell dysfunction.
The last decade has witnessed a growing appreciation of the fundamental role played by an early assembly of a diverse and balanced gut microbiota and its subsequent maintenance for future health of ...the host. Gut microbiota is currently viewed as a key regulator of a fluent bidirectional dialogue between the gut and the brain(gut-brain axis). A number of preclinical studies have suggested that the microbiota and its genome(microbiome) may play a key role in neurodevelopmental and neurodegenerative disorders. Furthermore, alterations in the gut microbiota composition in humans have also been linked to a variety of neuropsychiatric conditions, including depression, autism and Parkinson’s disease. However, it is not yet clear whether these changes in the microbiome are causally related to such diseases or are secondary effects thereof. In this respect, recent studies in animals have indicated that gut microbiota transplantation can transfer a behavioral phenotype, suggesting that the gut microbiota may be a modifiable factor modulating the development or pathogenesis of neuropsychiatric conditions. Further studies are warranted to establish whether or not the findings of preclinical animal experiments can be generalized to humans. Moreover, although different communication routes between the microbiota and brain have been identified, further studies must elucidate all the underlying mechanisms involved. Such research is expected to contribute to the design of strategies to modulate the gut microbiota and its functions with a view to improving mental health, and thus provide opportunities to improve the management of psychiatric diseases. Here, we review the evidence supporting a role of the gut microbiota in neuropsychiatric disorders and the state of the art regarding the mechanisms underlying its contribution to mental illness and health. We also consider the stages of life where the gut microbiota is more susceptible to the effects of environmental stressors, and the possible microbiota-targeted intervention strategies that could improve health status and prevent psychiatric disorders in the near future.
Breastfeeding protects against adverse cardiovascular outcomes in the long term. Melatonin is an active molecule that is present in the breast milk produced at night beginning in the first stages of ...lactation. This indoleamine appears to be a relevant contributor to the benefits of breast milk because it can affect infant health in several ways. The melatonin concentration in breast milk varies in a circadian pattern, making breast milk a chrononutrient. The consumption of melatonin can induce the first circadian stimulation in the infant’s body at an age when his/her own circadian machinery is not functioning yet. This molecule is also a powerful antioxidant with the ability to act on infant cells directly as a scavenger and indirectly by lowering oxidant molecule production and enhancing the antioxidant capacity of the body. Melatonin also participates in regulating inflammation. Furthermore, melatonin can participate in shaping the gut microbiota composition, richness, and variation over time, also modulating which molecules are absorbed by the host. In all these ways, melatonin from breast milk influences weight gain in infants, limiting the development of obesity and comorbidities in the long term, and it can help shape the ideal cellular environment for the development of the infant’s cardiovascular system.
Adipose tissue is recognized as an endocrine organ that secretes bioactive substances known as adipokines. Excess adipose tissue and adipose tissue dysfunction lead to dysregulated adipokine ...production that can contribute to the development of obesity-related co-morbidities. Among the various adipokines, resistin, which was initially considered as a determinant of the emergence of insulin resistance in obesity, has appeared as an important link between obesity and inflammatory processes. Several experimental and clinical studies have suggested an association between increased resistin levels and severe conditions associated with obesity such as cardiovascular disease and malignancies. In this review, we present the growing body of evidence that human resistin is an inflammatory biomarker and potential mediator of obesity-associated diseases. A common pathway seems to involve the combined alteration of immune and inflammatory processes that favor metabolic disturbances, atherosclerosis and carcinogenesis. The mode of action and the signaling pathways utilized by resistin in its interactions with target cells could involve oxidative and nitrosative stress. Therefore, resistin could function as a key molecule in the complications of obesity development and could potentially be used as a diagnostic and prognostic marker.
•Resistin has been proposed as a molecular link between obesity and IR.•Inflammation appears to be the main determinant of circulating levels of resistin.•Intracellular signaling for resistin converges in the activation of NF-κB and MAPK.•Increased oxidative stress is related to resistin.•Resistin may be a useful diagnostic and prognostic tool in obesity comorbidities.
The etiology of digestive pathologies such as irritable bowel syndrome (IBS), inflammatory bowel diseases (IBD) and cancer is not yet fully understood. In recent years, several studies have evidenced ...circadian variations in mechanisms involved in digestive health. In situations of disturbed circadian rhythms (chronodisruption) where the central clock and the peripheral clocks receive incoherent signals, the synchronicity is lost producing implications for health. This lack of coordination could alter the tissue function and cause long term damage to the organs. Life habits such as sleep, physical exercise, social interaction, and feeding times are determinants for stability and integrity of circadian rhythms. In recent years, experimental and clinical studies have consistently evidenced that the alteration of circadian rhythms is associated with the development of digestive pathologies mainly linked to dismotility or changes in microbiota composition. Likewise, it seems reasonable to deep into the importance of chronodisruption as a factor that may participate in the development of pathologies such as IBS, IBD and digestive cancers. Moreover, life habits respecting circadian rhythms should be promoted for the prevention of these diseases. Further studies will allow us a better understanding of the mechanisms acting at molecular level, and the development of new therapeutic targets.
Cross-sectional studies conducted with obese and control subjects have suggested associations between gut microbiota alterations and obesity, but the links with specific disease phenotypes and proofs ...of causality are still scarce. The present study aimed to profile the gut microbiota of lean and obese children with and without insulin resistance to characterize associations with specific obesity-related complications and understand the role played in metabolic inflammation. Through massive sequencing of 16S rRNA gene amplicons and data analysis using a novel permutation approach, we have detected decreased incidence of
species, especially
and
, in the gut microbiota of obese children, which was even more pronounced in cases with both obesity and insulin resistance. There was also a parallel increase in proinflammatory cytokines and chemokines (gamma interferon IFN-γ, tumor necrosis factor alpha TNF-α, and monocyte chemoattractant protein 1 MCP-1) in feces of obese children compared to those of lean ones.
and
were also shown to exert an anti-inflammatory effect in peripheral blood mononuclear cell cultures
, compared to non-obesity-associated species. We suggest that the depletion of
and
species in the gut ecosystem may occur in cases of obesity and contribute to metabolic inflammation leading to insulin resistance.
Child obesity constitutes a risk factor for developing insulin resistance which, if sustained, could lead to more severe conditions like type 2 diabetes (T2D) in adulthood. Our study identified previously unknown species whose depletion (
and
) is associated with insulin resistance in obese individuals. Our results also indicate that these bacterial species might help to reduce inflammation causally linked to obesity-related complications. Childhood is considered a window of opportunity to tackle obesity. These new findings provide, therefore, valuable information for the future design of microbiota-based strategies for the early prevention of obesity-related complications.
It is widely recognized that the intestinal microbiota plays a role in the initiation and perpetuation of intestinal inflammation in numerous chronic conditions. Most studies report intestinal ...dysbiosis in celiac disease (CD) patients, untreated and treated with a gluten-free diet (GFD), compared to healthy controls. CD patients with gastrointestinal symptoms are also known to have a different microbiota compared to patients with dermatitis herpetiformis and controls, suggesting that the microbiota is involved in disease manifestation. Furthermore, a dysbiotic microbiota seems to be associated with persistent gastrointestinal symptoms in treated CD patients, suggesting its pathogenic implication in these particular cases. GFD per se influences gut microbiota composition, and thus constitutes an inevitable confounding factor in studies conducted in CD patients. To improve our understanding of whether intestinal dysbiosis is the cause or consequence of disease, prospective studies in healthy infants at family risk of CD are underway. These studies have revealed that the CD host genotype selects for the early colonizers of the infant's gut, which together with environmental factors (e.g., breast-feeding, antibiotics, etc.) could influence the development of oral tolerance to gluten. Indeed, some CD genes and/or their altered expression play a role in bacterial colonization and sensing. In turn, intestinal dysbiosis could promote an abnormal response to gluten or other environmental CD-promoting factors (e.g., infections) in predisposed individuals. Here, we review the current knowledge of host-microbe interactions and how host genetics/epigenetics and environmental factors shape gut microbiota and may influence disease risk. We also summarize the current knowledge about the potential mechanisms of action of the intestinal microbiota and specific components that affect CD pathogenesis.
Evidence of obesity-induced oxidative stress in adults has emerged in the past several years, and similar evidence has been demonstrated in children more recently. The reactive species of oxygen or ...nitrogen can chemically alter all major classes of biomolecules by modifying their structure and function. Organisms have developed mechanisms to protect biomolecules from the deleterious effects of free radicals. These include the enzymes superoxide dismutase, catalase, and glutathione peroxidase, as well as water and lipid-soluble antioxidants, such as glutathione, ascorbate (vitamin C), α-tocopherol (vitamin E), and β-carotene. Obesity creates oxidant conditions that favor the development of comorbid diseases. Energy imbalances lead to the storage of excess energy in adipocytes, resulting in both hypertrophy and hyperplasia. These processes are associated with abnormalities of adipocyte function, particularly mitochondrial stress and disrupted endoplasmic reticulum function. In this sense, oxidative stress can also be induced by adipocyte associated inflammatory macrophages. There is a close link among obesity, a state of chronic low-level inflammation, and oxidative stress. In addition, the dysregulation of adipocytokines, which are secreted by adipose tissue and promoted by oxidative stress, act synergistically in obesity-related metabolic abnormalities. Adipocytokines link the local and systemic inflammation responses in the context of obesity. It is thought that the evaluation of oxidative status may allow for the identification of patients at an increased risk of complications. Decreasing the levels of chronic inflammation and oxidative stress in childhood may decrease cardiovascular morbidity and mortality in adulthood.
Recent data suggest that retinol-binding protein 4 (RBP4) gene variants could be associated with a risk of obesity and its co-morbidities, such as metabolic syndrome, which increases the risk of ...developing type 2 diabetes mellitus and cardiovascular disease.
The present study examined the potential association of RBP4 single nucleotide polymorphisms (SNPs) with childhood obesity and its metabolic complications.
Four RBP4 SNPs, rs3758538 (3944A>C), rs3758539 (4406G>A), rs12265684 (12177G>C) and rs34571439 (14684T>G), were genotyped in a population of 180 Spanish Caucasian children (97 obese and 83 normal-weight children). Association of RBP4 SNPs with obesity, metabolic risk factors (blood pressure, triglycerides, high-density lipoprotein cholesterol, insulin resistance) and markers of vascular inflammation, such as high-sensitive C-reactive protein (hs-CRP), was tested.
We found SNP rs3758538 to be associated with obesity (p = 0.007). Specifically, each copy of the minor allele C was associated with an increased risk of obesity, by more than twofold, in respect of being homozygous for the major allele A (odds ratio = 2.4; 95% confidence interval = 1.2-4.8). The rs3758538 and rs34571439 RBP4 SNPs correlated with plasma RBP4 levels. The SNPs rs12265684 and rs34571439 correlated with plasma triglyceride levels. The rs34571439 was also associated to hs-CRP levels. Marginal association of RBP4 SNPs with plasma high-density lipoprotein levels (rs34571439), blood pressure (rs12265684) and insulin resistance (rs3758539) was also observed.
These findings suggest that childhood obesity may be associated with variations in RBP4 gene. The presence of selective SNPs in the RBP4 gene may account for metabolic complications.
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