scholarly journals Autophagy in health and disease. 2. Regulation of lipid metabolism and storage by autophagy: pathophysiological implications

2010 ◽  
Vol 298 (5) ◽  
pp. C973-C978 ◽  
Author(s):  
Mark J. Czaja

Autophagy is a lysosomal degradative pathway critical for the removal and breakdown of cellular components such as organelles and proteins. Despite striking similarities in the regulation and function of autophagy and lipid metabolism, the two processes have only recently been shown to be interrelated. This review details new findings of critical functions for autophagy in lipid metabolism and storage. Studies in hepatocytes and liver have demonstrated that macroautophagy mediates the breakdown of lipids stored in lipid droplets and that an inhibition of autophagy leads to the development of a fatty liver. In contrast, in adipocytes the loss of macroautophagy decreases the amount of lipid stored in adipose tissue through effects on white and brown adipocyte differentiation. Other investigations have indicated that the relationship between autophagy and lipids is bidirectional, with changes in cellular lipid content altering autophagic function. These newly described links between autophagy and lipid metabolism and storage have provided new insights into the mechanisms of both processes. The findings also suggest possible new therapeutic approaches to the problems of lipid overaccumulation and impaired autophagy that occur with aging and the metabolic syndrome.

Cells ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 126
Author(s):  
Annalisa Bosi ◽  
Davide Banfi ◽  
Michela Bistoletti ◽  
Paola Moretto ◽  
Elisabetta Moro ◽  
...  

The commensal microbiota plays a fundamental role in maintaining host gut homeostasis by controlling several metabolic, neuronal and immune functions. Conversely, changes in the gut microenvironment may alter the saprophytic microbial community and function, hampering the positive relationship with the host. In this bidirectional interplay between the gut microbiota and the host, hyaluronan (HA), an unbranched glycosaminoglycan component of the extracellular matrix, has a multifaceted role. HA is fundamental for bacterial metabolism and influences bacterial adhesiveness to the mucosal layer and diffusion across the epithelial barrier. In the host, HA may be produced and distributed in different cellular components within the gut microenvironment, playing a role in the modulation of immune and neuronal responses. This review covers the more recent studies highlighting the relevance of HA as a putative modulator of the communication between luminal bacteria and the host gut neuro-immune axis both in health and disease conditions, such as inflammatory bowel disease and ischemia/reperfusion injury.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7224 ◽  
Author(s):  
Héla Mkaouar ◽  
Nizar Akermi ◽  
Aicha Kriaa ◽  
Anne-Laure Abraham ◽  
Amin Jablaoui ◽  
...  

Serine Protease Inhibitors (Serpins) control tightly regulated physiological processes and their dysfunction is associated to various diseases. Thus, increasing interest is given to these proteins as new therapeutic targets. Several studies provided functional and structural data about human serpins. By comparison, only little knowledge regarding bacterial serpins exists. Through the emergence of metagenomic studies, many bacterial serpins were identified from numerous ecological niches including the human gut microbiota. The origin, distribution and function of these proteins remain to be established. In this report, we shed light on the key role of human and bacterial serpins in health and disease. Moreover, we analyze their function, phylogeny and ecological distribution. This review highlights the potential use of bacterial serpins to set out new therapeutic approaches.


Author(s):  
Natalia Di Tommaso ◽  
Antonio Gasbarrini ◽  
Francesca Romana Ponziani

The intestinal mucosa provides a selective permeable barrier for nutrient absorption and protection from external factors. It consists of epithelial cells, immune cells and their secretions. The gut microbiota participates in regulating the integrity and function of the intestinal barrier in a homeostatic balance. Pathogens, xenobiotics and food can disrupt the intestinal barrier, promoting systemic inflammation and tissue damage. Genetic and immune factors predispose individuals to gut barrier dysfunction, and changes in the composition and function of the gut microbiota are central to this process. The progressive identification of these changes has led to the development of the concept of ‘leaky gut syndrome’ and ‘gut dysbiosis’, which underlie the relationship between intestinal barrier impairment, metabolic diseases and autoimmunity. Understanding the mechanisms underlying this process is an intriguing subject of research for the diagnosis and treatment of various intestinal and extraintestinal diseases.


Kidney360 ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 755-762
Author(s):  
Jin-Ju Kim ◽  
Sydney S. Wilbon ◽  
Alessia Fornoni

CKD represents the ninth most common cause of death in the United States but, despite this large health burden, treatment options for affected patients remain limited. To remedy this, several relevant pathways have been identified that may lead to novel therapeutic options. Among them, altered renal lipid metabolism, first described in 1982, has been recognized as a common pathway in clinical and experimental CKD of both metabolic and nonmetabolic origin. This observation has led many researchers to investigate the cause of this renal parenchyma lipid accumulation and its downstream effect on renal structure and function. Among key cellular components of the kidney parenchyma, podocytes are terminally differentiated cells that cannot be easily replaced when lost. Clinical and experimental evidence supports a role of reduced podocyte number in the progression of CKD. Given the importance of the podocytes in the maintenance of the glomerular filtration barrier and the accumulation of TG and cholesterol-rich lipid droplets in the podocyte and glomerulus in kidney diseases that cause CKD, understanding the upstream cause and downstream consequences of lipid accumulation in podocytes may lead to novel therapeutic opportunities. In this review, we hope to consolidate our understanding of the causes and consequences of dysregulated renal lipid metabolism in CKD development and progression, with a major focus on podocytes.


Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2532
Author(s):  
Mari C. Vázquez-Borrego ◽  
Mercedes del Rio-Moreno ◽  
Rhonda D. Kineman

Growth hormone (GH) is critical for achieving normal structural growth. In addition, GH plays an important role in regulating metabolic function. GH acts through its GH receptor (GHR) to modulate the production and function of insulin-like growth factor 1 (IGF1) and insulin. GH, IGF1, and insulin act on multiple tissues to coordinate metabolic control in a context-specific manner. This review will specifically focus on our current understanding of the direct and indirect actions of GH to control liver (hepatocyte) carbohydrate and lipid metabolism in the context of normal fasting (sleep) and feeding (wake) cycles and in response to prolonged nutrient deprivation and excess. Caveats and challenges related to the model systems used and areas that require further investigation towards a clearer understanding of the role GH plays in metabolic health and disease are discussed.


2006 ◽  
Vol 111 (2) ◽  
pp. 107-118 ◽  
Author(s):  
Shanhong Ling ◽  
Paul Komesaroff ◽  
Krishnankutty Sudhir

Although pre-menopausal women enjoy relative cardiovascular protection, hormone (oestrogen±progestin)-replacement therapy has not shown cardiovascular benefits in post-menopausal women, suggesting that the effects of oestrogens on the cardiovascular system are much more complex than previously expected. Endothelial cells, smooth muscle cells, cardiac myocytes and fibroblasts, the cellular components of blood vessels and the heart, play important roles in cardiovascular health and disease. During the development and progression of cardiovascular disease, changes occur both in the structure and function of these cells, resulting in a wide range of abnormalities, which affect growth, death and physiological function. These cells contain functional oestrogen receptors and are targets for oestrogen action. This review focuses on recent studies on the effects of oestrogen on cardiovascular cell function. Oestrogens, particularly 17β-oestradiol, exert multiple effects on cardiovascular cells, and these effects may contribute to the gender-associated protection against cardiovascular diseases.


2012 ◽  
Vol 13 (1) ◽  
pp. 121-128 ◽  
Author(s):  
Marcio C. Costa ◽  
J. Scott Weese

AbstractThe equine intestinal tract contains a complex microbial population (microbiota) that plays an important role in health and disease. Despite the undeniable importance of a ‘normal’ microbiota, understanding of the composition and function of this population is currently limited. As methods to characterize the microbiota and its genetic makeup (the microbiome) have evolved, the composition and complexity of this population are starting to be revealed. As is befitting a hindgut fermenter, members of the Firmicutes phylum appear to predominate, yet there are significant populations of numerous other phyla. The microbiome appears to be profoundly altered in certain disease states, and better understanding of these alterations may offer hope for novel preventive and therapeutic measures. The development and increasing availability of next generation sequencing and bioinformatics methods offer a revolution in microbiome evaluation and it is likely that significant advances will be made in the near future. Yet, proper use of these methods requires further study of basic aspects such as optimal testing protocols, the relationship of the fecal microbiome to more proximal locations where disease occurs, normal intra- and inter-horse variation, seasonal variation, and similar factors.


Author(s):  
Patricia G. Arscott ◽  
Gil Lee ◽  
Victor A. Bloomfield ◽  
D. Fennell Evans

STM is one of the most promising techniques available for visualizing the fine details of biomolecular structure. It has been used to map the surface topography of inorganic materials in atomic dimensions, and thus has the resolving power not only to determine the conformation of small molecules but to distinguish site-specific features within a molecule. That level of detail is of critical importance in understanding the relationship between form and function in biological systems. The size, shape, and accessibility of molecular structures can be determined much more accurately by STM than by electron microscopy since no staining, shadowing or labeling with heavy metals is required, and there is no exposure to damaging radiation by electrons. Crystallography and most other physical techniques do not give information about individual molecules.We have obtained striking images of DNA and RNA, using calf thymus DNA and two synthetic polynucleotides, poly(dG-me5dC)·poly(dG-me5dC) and poly(rA)·poly(rU).


2011 ◽  
Vol 21 (3) ◽  
pp. 112-117 ◽  
Author(s):  
Elizabeth Erickson-Levendoski ◽  
Mahalakshmi Sivasankar

The epithelium plays a critical role in the maintenance of laryngeal health. This is evident in that laryngeal disease may result when the integrity of the epithelium is compromised by insults such as laryngopharyngeal reflux. In this article, we will review the structure and function of the laryngeal epithelium and summarize the impact of laryngopharyngeal reflux on the epithelium. Research investigating the ramifications of reflux on the epithelium has improved our understanding of laryngeal disease associated with laryngopharyngeal reflux. It further highlights the need for continued research on the laryngeal epithelium in health and disease.


Gesnerus ◽  
2019 ◽  
Vol 76 (2) ◽  
pp. 172-191
Author(s):  
Susanne Vollberg

In the television programme of West Germany from the 1960s to the 1980s, health magazines like Gesundheitsmagazin Praxis [Practice Health Magazine] (produced by ZDF)1 or ARD-Ratgeber: Gesundheit [ARD Health Advisor] played an important role in addressing health and disease as topics of public awareness. With their health magazine Visite [Doctor’s rounds], East German television, too relied on continuous coverage and reporting in the field. On the example of above magazines, this paper will examine the history, design and function of health communication in magazine-type formats. Before the background of the changes in media policy experienced over three decades and the different media systems in the then two Germanys, it will discuss the question of whether television was able to move health relevant topics and issues into public consciousness.


Sign in / Sign up

Export Citation Format

Share Document