The 10 most-cited articles in Experimental Biology and Medicine, 2018

Biomarkers are critical to the rational development of medical therapeutics, but significant confusion persists regarding fundamental definitions and concepts involved in their use in research and clinical practice, particularly in the fields of chronic disease and nutrition. Clarification of the definitions of different biomarkers and a better understanding of their appropriate application could result in substantial benefits. This review examines biomarker definitions recently established by the U.S. Food and Drug Administration and the National Institutes of Health as part of their joint Biomarkers, EndpointS, and other Tools (BEST) resource. These definitions are placed in context of their respective uses in patient care, clinical research, or therapeutic development. We explore the distinctions between biomarkers and clinical outcome assessments and discuss the specific definitions and applications of diagnostic, monitoring, pharmacodynamic/response, predictive, prognostic, safety, and susceptibility/risk biomarkers. We also explore the implications of current biomarker…

Prenatal and postnatal myogenesis share many cellular and molecular aspects. Myogenic regulatory factors are basic Helix-Loop-Helix transcription factors that indispensably regulate both processes. These factors (Myf5, MyoD, Myogenin, and MRF4) function as an orchestrating cascade, with some overlapped actions. Prenatally, myogenic regulatory factors are restrictedly expressed in somite-derived myogenic progenitor cells and their derived myoblasts. Postnatally, myogenic regulatory factors are important in regulating the myogenesis process via satellite cells. Many positive and negative regulatory mechanisms exist either between myogenic regulatory factors themselves or between myogenic regulatory factors and other proteins. Upstream factors and signals are also involved in the control of myogenic regulatory factors expression within different prenatal and postnatal myogenic cells. Here, the authors have conducted a thorough and an up-to-date review of the myogenic regulatory factors since their discovery 30 years ago. This review discusses the myogenic regulatory factors structure,…

Maternal nutrition during gestation, especially dietary protein intake, is a key determinant in embryonic survival, growth, and development. Low maternal dietary protein intake can cause embryonic losses, intra-uterine growth restriction, and reduced postnatal growth due to a deficiency in specific amino acids that are important for cell metabolism and function. Of note, high maternal dietary protein intake can also result in intra-uterine growth restriction and embryonic death, due to amino acid excesses, as well as the toxicity of ammonia, homocysteine, and H 2 S that are generated from amino acid catabolism. Maternal protein nutrition has a pronounced impact on fetal programming and alters the expression of genes in the fetal genome. As a precursor to the synthesis of molecules (e.g. nitric oxide, polyamines, and creatine) with cell signaling and metabolic functions, L-arginine (Arg) is essential during pregnancy for growth and development of the conceptus. With inadequate maternal dietary protein intake, Arg and other important amino acids are deficient in mother and fetus.…

Dysbiosis, a broad spectrum of imbalance of the gut microbiota, may progress to microbiota dysfunction. Dysbiosis is linked to some human diseases, such as inflammation-related disorders and metabolic syndromes. However, the underlying mechanisms of the pathogenesis of dysbiosis remain elusive. Recent findings suggest that the microbiome and gut immune responses, like immunoglobulin A production, play critical roles in the gut homeostasis and function, and the progression of dysbiosis. In the past two decades, much progress has been made in better understanding of production of immunoglobulin A and its association with commensal microbiota. The present minireview summarizes the recent findings in the gut microbiota dysbiosis and dysfunction of immunoglobulin A induced by the imbalance of pathogenic bacteria and commensal microbiota. We also propose the potentials of dietary carotenoids, such as β-carotene and astaxanthin, in the improvement of the gut immune system maturation and immunoglobulin A production, and the consequent promotion of the gut health. Impact statement The…

Inflammatory processes are increasingly being identified at the core of many different disease states (e.g. heart disease, cancer, diabetes). As such, anti-inflammatory strategies available through drug delivery have undergone renewed interest. Due to the systemic side effects of steroidal drugs, non-steroidal anti-inflammatory drugs are often preferred for long-term treatment of inflammation in a variety of applications. While non-steroidal anti-inflammatory drugs are generally safe, there are some serious side effects that can be associated with their usage, particularly when given systemically or orally. Due to the high number of patients taking non-steroidal anti-inflammatory drugs, the reduction or elimination of these side effects, such as is possible through local drug delivery, could have a very powerful effect on patient quality of life. This review comments on a sampling of existing methods for localized or targeted delivery of non-steroidal anti-inflammatory drugs, with the goal of helping future research groups to focus on bettering methods shown to be effective and…

Intermittent fasting may be an effective intervention to protect against age-related metabolic disturbances, although it is still controversial. Here, we investigated the effect of intermittent fasting on the deterioration of the metabolism and cognitive functions in rats with estrogen deficiency and its mechanism was also explored. Ovariectomized rats were infused with β-amyloid (25-35; Alzheimer's disease) or β-amyloid (35-25, Non-Alzheimer's disease; normal cognitive function) into the hippocampus. Each group was randomly divided into two sub-groups: one with intermittent fasting and the other fed ad libitum: Alzheimer's disease-ad libitum, Alzheimer's disease-intermittent fasting, Non-Alzheimer's disease-ad libitum, and Non-Alzheimer's disease-intermittent fasting. Rats in the intermittent fasting groups had a restriction of food consumption to a 3-h period every day. Each group included 10 rats and all rats fed a high-fat diet for four weeks. Interestingly, Alzheimer's disease increased tail skin temperature more than Non-Alzheimer's disease and intermittent fasting prevented…

Numerous studies have examined the association between body mass index and mortality and often observed that risk of mortality was higher in those with lower body mass index than those who were overweight or even obese (“obesity paradox”). One potential explanation of the obesity paradox is the limitation of body mass index as an imperfect measure of adiposity. However, relatively few studies have examined the association between body composition and mortality due to practical issues of assessing body composition in large-scale epidemiological settings. The available epidemiologic studies on this topic were heterogenous with regard to study design, analyses, results, and interpretations. The majority of studies using direct body composition measures such as dual-energy x-ray absorptiometry or computed tomography had relatively small sample size, short follow-up period and restricted study population. Studies have also used other approaches to indirectly estimate body composition to examine the association with mortality in a larger and more representative population. Overall…

Progress in microbiome research has accelerated in recent years. Through the use of 16S rRNA assays and other genomic sequencing techniques, researchers have provided new insights about the communities of microorganisms that inhabit human and animal hosts. There is mounting evidence about the importance of these ‘microbiotas’ in a wide variety of disease states, suggesting potential targets for preventative and therapeutic interventions. Until recently, however, the microbiome received relatively little attention in ophthalmology. This review explores emerging research on the roles that ocular and extraocular microbiotas may play in the pathogenesis and treatment of ophthalmic diseases. These include diseases of the ocular surface as well as autoimmune uveitis, age-related macular degeneration, and primary open angle glaucoma. Many questions remain about the potential impacts of microbiome research on the diagnosis, treatment, and prevention of ophthalmic disease. In light of current findings, we suggest directions for future study as this exciting area of research continues to…

Sex-based disparities have been identified in respiratory physiology, and in many chronic lung diseases including asthma, chronic obstructive pulmonary disease, and cystic fibrosis. The observed sex differences in lung disease prevalence and incidence have been linked to changes in circulating levels of sex hormones that start after puberty and that have been shown to affect physiological and immunological functions. While the exact roles of male and female sex hormones in these processes have not been fully elucidated, it is now evident that these can target many lung cell types and affect several functions of the respiratory system. In this mini-review, we have summarized seminal studies aimed to understand the effects of the most relevant male and female sex hormones (estrogens, progesterone, and androgens) and their receptors on lung function. Moreover, we have reviewed the known influences of sex hormones and of the hypothalamic–pituitary–gonadal axis in lung disease and immunity. Understanding the roles of sex hormones in the regulation of lung function and inflammation is the…

Inflammatory bowel disease is a complex collection of disorders. Microbial dysbiosis as well as exposure to toxins including xenoestrogens are thought to be risk factors for inflammatory bowel disease development and relapse. Bisphenol-A has been shown to exert estrogenic activity in the colon and alter intestinal function, but the role that xenoestrogens, such as bisphenol-A , play in colonic inflammation has been previously described but with conflicting results. We investigated the ability of bisphenol-A to exacerbate colonic inflammation and alter microbiota metabolites derived from aromatic amino acids in an acute dextran sulfate sodium-induced colitis model. Female C57BL/6 mice were ovariectomized and exposed to bisphenol-A daily for 15 days. Disease activity measures include body weight, fecal consistency, and rectal bleeding. Colons were scored for inflammation, injury, and nodularity. Alterations in the levels of microbiota metabolites derived from aromatic amino acids known to reflect phenotypic changes in the gut microbiome were analyzed. Bisphenol-A exposure increased…