Increased ghrelin signaling prolongs survival in mouse models of human aging through activation of sirtuin1

Skeletal Muscle Injury in Chronic Kidney Disease-From Histologic Changes to Molecular Mechanisms and to Novel Therapies

Chronic kidney disease (CKD) is associated with significant reductions in lean body mass and in the mass of various tissues, including skeletal muscle, which causes fatigue and contributes to high mortality rates. In CKD, the cellular protein turnover is imbalanced, with protein degradation outweighing protein synthesis, leading to a loss of protein and cell mass, which impairs tissue function. As CKD itself, skeletal muscle wasting, or sarcopenia, can have various origins and causes, and both CKD and sarcopenia share common risk factors, such as diabetes, obesity, and age. While these pathologies together with reduced physical performance and malnutrition contribute to muscle loss, they cannot explain all features of CKD-associated sarcopenia. Metabolic acidosis, systemic inflammation, insulin resistance and the accumulation of uremic toxins have been identified as additional factors that occur in CKD and that can contribute to sarcopenia. Here, we discuss the elevation of systemic phosphate levels, also called hyperphosphatemia, and the imbalance in the endocrine regulators of phosphate metabolism as another CKD-associated pathology that can directly and indirectly harm skeletal muscle tissue. To identify causes, affected cell types, and the mechanisms of sarcopenia and thereby novel targets for therapeutic interventions, it is important to first characterize the precise pathologic changes on molecular, cellular, and histologic levels, and to do so in CKD patients as well as in animal models of CKD, which we describe here in detail. We also discuss the currently known pathomechanisms and therapeutic approaches of CKD-associated sarcopenia, as well as the effects of hyperphosphatemia and the novel drug targets it could provide to protect skeletal muscle in CKD.

Microbiota-gut-brain axis and its therapeutic applications in neurodegenerative diseases

The human gastrointestinal tract is populated with a diverse microbial community. The vast genetic and metabolic potential of the gut microbiome underpins its ubiquity in nearly every aspect of human biology, including health maintenance, development, aging, and disease. The advent of new sequencing technologies and culture-independent methods has allowed researchers to move beyond correlative studies toward mechanistic explorations to shed light on microbiome-host interactions. Evidence has unveiled the bidirectional communication between the gut microbiome and the central nervous system, referred to as the "microbiota-gut-brain axis". The microbiota-gut-brain axis represents an important regulator of glial functions, making it an actionable target to ameliorate the development and progression of neurodegenerative diseases. In this review, we discuss the mechanisms of the microbiota-gut-brain axis in neurodegenerative diseases. As the gut microbiome provides essential cues to microglia, astrocytes, and oligodendrocytes, we examine the communications between gut microbiota and these glial cells during healthy states and neurodegenerative diseases. Subsequently, we discuss the mechanisms of the microbiota-gut-brain axis in neurodegenerative diseases using a metabolite-centric approach, while also examining the role of gut microbiota-related neurotransmitters and gut hormones. Next, we examine the potential of targeting the intestinal barrier, blood-brain barrier, meninges, and peripheral immune system to counteract glial dysfunction in neurodegeneration. Finally, we conclude by assessing the pre-clinical and clinical evidence of probiotics, prebiotics, and fecal microbiota transplantation in neurodegenerative diseases. A thorough comprehension of the microbiota-gut-brain axis will foster the development of effective therapeutic interventions for the management of neurodegenerative diseases.

Japanese Traditional Herbal Medicine, Rikkunshito, Partially Suppresses Inflammatory Responses in Myocardial Ischemia/Reperfusion Injury

INTRODUCTION

Myocardial ischemia/reperfusion (I/R) injury can cause additional damage to an ischemic myocardium, even after successful reperfusion therapy. Inflammation is a mechanism that exacerbates myocardial damage after I/R injury. Rikkunshito (RKT) is a traditional Japanese herbal medicine widely used to treat gastrointestinal symptoms. It attenuates inflammation and fibrosis in some diseases of the heart; however, it remains unclear whether RKT exerts cardioprotective effects against myocardial I/R injury. To elucidate this, we evaluated the effects of RKT pre-treatment by oral administration on the myocardium in a mouse model of in vivo I/R injury.

METHODS

Mice were randomly assigned to a group receiving distilled water (DW) or one receiving RKT (1000 mg/kg/day) for 14 days orally. For each of the RKT and DW groups, a sham group, an I/R 2 h group, and an I/R 24 h group were created. On day 15, myocardial I/R surgery was performed. The left anterior descending coronary artery (LAD) was ligated for 30 min, and reperfusion time was set at 2 h or 24 h. The myocardial infarct size (IS) was measured after 2 h of reperfusion, and cardiac cytokine mRNA expression levels were evaluated by quantitative reverse transcription polymerase chain reaction (RT-PCR) after 2 h and 24 h of reperfusion.

RESULTS

RKT pre-treatment significantly suppressed the cardiac mRNA expression level of interleukin-1β in the RKT-I/R 2 h group compared to the DW-I/R 2 h group (P < 0.05). Additionally, RKT significantly suppressed the mRNA expression levels of transforming growth factor-β compared to DW; the same result was obtained for the expression levels of interleukin-6. However, RKT did not reduce the IS or mRNA expression levels of the cardiac congestive markers natriuretic peptide a (NPPA) and natriuretic peptide b (NPPB). In addition, RKT did not alter the plasma concentration of ghrelin and sirtuin 1 (Sirt1), which have been reported to be stimulated by RKT.

CONCLUSION

This study showed that pre-treatment of RKT for myocardial I/R injury partially suppressed inflammation-related cytokines. However, further studies are needed on the effect of RKT on the reduction of myocardial infarction size.

Emerging role of α-Klotho in energy metabolism and cardiometabolic diseases

BACKGROUND AND AIM

Klotho was first identified as a gene associated with aging and longevity in 1997. α-Klotho is an anti-aging protein and its role in energy metabolism, various cardiovascular diseases (CVDs), and metabolic disorders is increasingly being recognized. In this review, we aimed to outline the potential protective role and therapeutic prospects of α-Klotho in energy metabolism and cardiometabolic diseases (CMDs).

METHODS

We comprehensively reviewed the relevant literature in PubMed using the keywords 'Klotho', 'metabolism', 'cardiovascular', 'diabetes', 'obesity', 'metabolic syndrome', and 'nonalcoholic fatty liver disease'.

RESULTS

α-Klotho can be divided into membrane-bound Klotho, secreted Klotho, and the most studied circulating soluble Klotho that can act as a hormone. Klotho gene polymorphisms have been implicated in energy metabolism and CMDs. α-Klotho can inhibit insulin/insulin growth factor-1 signaling and its overexpression can lead to a 'healthy insulin resistance' and may exert beneficial effects on the regulation of glycolipid metabolism and central energy homeostasis. α-Klotho, mainly serum Klotho, has been revealed to be protective against CVDs, diabetes and its complications, obesity, and nonalcoholic fatty liver disease. Human recombinant Klotho protein/Klotho gene delivery, multiple drugs, or natural products, and exercise can increase α-Klotho expression.

CONCLUSION

Overall, α-Klotho has demonstrated its potential as a promising target for modulating energy metabolism and CMDs, and further research is needed to explore its utilization in clinical practice in the future.

Soy-fortelin: A ghrelin sensitivity-enhancing peptide that stimulates food intake in aged mice

Ghrelin sensitivity is known to decrease with aging in mice and humans, and the decrease contributes to anorexia with aging. In this study, we discovered novel ghrelin sensitivity-enhancing peptides. Ghrelin sensitivity was evaluated by examining whether dipeptide samples enhanced the calcium response to ghrelin in the growth hormone secretagogue receptor-transfected cell line. First, dipeptides were screened using a 336-dipeptide library and we revealed that Ser-Tyr (SY) potentiated ghrelin sensitivity in particular. Based on the structure-activity relationship determined using the dipeptide library and comprehensive analysis of peptides in the chymotrypsin digest of soy β-conglycinin (β-CG), which enhanced ghrelin sensitivity, candidate peptides were narrowed down. Among the chemosynthesized peptides, we discovered that an undecapeptide, SLVNNDDRDSY, corresponding to β-CGα(267-277), stimulated ghrelin sensitivity in vitro. This peptide enhanced the orexigenic activity of ghrelin in C57BL/6 mice and stimulated food intake. Thus, we demonstrated that SLVNNDDRDSY stimulated ghrelin sensitivity in vitro and in vivo and named it "soy-fortelin". Moreover, orally administered soy-fortelin had a similar but smaller effect in the young C57BL/6 mice, whereas it strongly stimulated food intake in 2-year-old aged mice that exhibited high blood ghrelin levels and low ghrelin sensitivity. In conclusion, we discovered soy-fortelin as a novel peptide that enhances ghrelin sensitivity in vivo and in vitro and increases food intake in young and aged ghrelin-resistant mice. Soy-fortelin is the first food-derived peptide reported to enhance ghrelin sensitivity.

The effect of a pharmaceutical ghrelin agonist on lifespan in C57BL/6J male mice: A controlled experiment

Interventions for animal lifespan extension like caloric restriction (CR) have identified physiologic and biochemical pathways related to hunger and energy-sensing status as possible contributors, but mechanisms have not been fully elucidated. Prior studies using ghrelin agonists show greater food intake but no effect on lifespan in rodent models. This experiment in male C57BL/6J mice tested the influence of ghrelin agonism for perceived hunger, in the absence of CR, on longevity. Mice aged 4 weeks were allowed to acclimate for 2 weeks prior to being assigned (N = 60/group). Prior to lights off daily (12:12 cycle), animals were fed a ghrelin agonist pill (LY444711; Eli Lilly) or a placebo control (Ctrl) until death. Treatment (GhrAg) animals were pair-fed daily based on the group mean food intake consumed by Ctrl (ad libitum feeding) the prior week. Results indicate an increased lifespan effect (log-rank p = 0.0032) for GhrAg versus placebo Ctrl, which weighed significantly more than GhrAg (adjusted for baseline weight). Further studies are needed to determine the full scope of effects of this ghrelin agonist, either directly via increased ghrelin receptor signaling or indirectly via other hypothalamic, systemic, or tissue-specific mechanisms.

Impact of Ninjin’yoeito on frailty and short life in klotho-hypomorphic (kl/kl) mice

With the recent aging of society, the prevention of frailty has become an important issue because people desire both a long and healthy lifespan. Klotho-hypomorphic (kl/kl) mice are known to show phenotypes of premature aging. Ninjin’yoeito (NYT) is a traditional Japanese Kampo medicine used to treat patients with vulnerable constitution, fatigue or physical exhaustion caused by aging and illness. Recent studies have reported the potential efficacy of NYT against frailty. We therefore evaluated the effect of NYT on the gait function, activity, the histopathological status of organs and survival using kl/kl mice as a model of aging-related frailty. Two sets of 28-day-old male kl/kl mice were assigned to the vehicle (non-treated; NT), 3% or 5% NYT dietary groups. One set of groups (NT, n = 18; 3% NYT, n = 11; 5% NYT, n = 11) was subjected to the analysis of free walking, rotarod, and spontaneous activity tests at approximately 58 days old. Thereafter, we measured triceps surae muscles weight and myofiber cross-sectional area (CSA), and quantified its telomere content. In addition, we evaluated bone strength and performed histopathological examinations of organs. Survival was measured in the second set of groups (NT, 3% NYT and 5% NYT group, n = 8 each). In the walking test, several indicators such as gait velocity were improved in the NYT 3% group. Similar results were obtained for the latency to fall in the rotarod test and spontaneous motor activity. Triceps muscle mass, CSA and its telomere content were significantly improved in the NYT 3% group. Bone density, pulmonary alveolus destruction and testicular atrophy were also significantly improved in the NYT 3% group. Survival rate and body weight were both significantly improved in the NYT3% group compared with those in the NT group. Continuous administration of NYT from the early stage of aging improved not only gait performance, but also the survival in the aging-related frailty model. This effect may be associated with the improvements in aging-related organ changes such as muscle atrophy. Intervention with NYT against the progression of frailty may contribute to a longer, healthier life span among the elderly individuals.

Endogenous Vasoactive Peptides and Vascular Aging-Related Diseases

Vascular aging is a specific type of organic aging that plays a central role in the morbidity and mortality of cardiovascular and cerebrovascular diseases among the elderly. It is essential to develop novel interventions to prevent/delay age-related vascular pathologies by targeting fundamental cellular and molecular aging processes. Endogenous vasoactive peptides are compounds formed by a group of amino acids connected by peptide chains that exert regulatory roles in intercellular interactions involved in a variety of biological and pathological processes. Emerging evidence suggests that a variety of vasoactive peptides play important roles in the occurrence and development of vascular aging and related diseases such as atherosclerosis, hypertension, vascular calcification, abdominal aortic aneurysms, and stroke. This review will summarize the cumulative roles and mechanisms of several important endogenous vasoactive peptides in vascular aging and vascular aging-related diseases. In addition, we also aim to explore the promising diagnostic function as biomarkers and the potential therapeutic application of endogenous vasoactive peptides in vascular aging-related diseases.

Effects of Kampo medicine hangebyakujutsutemmato on persistent postural-perceptual dizziness: A retrospective pilot study

BACKGROUND

Persistent postural-perceptual dizziness (PPPD) is a functional disorder, typically preceded by acute vestibular disorders. It is characterized by a shift in processing spatial orientation information, to favor visual over vestibular and somatosensory inputs, and a failure of higher cortical mechanisms. To date, no therapies for PPPD have been approved. Kampo medicine hangebyakujutsutemmato (HBT) has been reported to alleviate disturbances of equilibrium. We hypothesized that HBT would be a beneficial treatment for PPPD.

AIM

To examine the efficacy of HBT for the treatment of PPPD.

METHODS

Patients with PPPD were enrolled and divided into two groups: The HBT group (n = 24) and the non-HBT group (n = 14). The participants completed questionnaire surveys [Niigata PPPD questionnaire (NPQ), dizziness handicap inventory, hospital anxiety and depression scale (HADS), orthostatic dysregulation questionnaire, pittsburg sleep quality index (PSQI), and motion sickness scores] before and after HBT treatment. Additionally, to identify HBT responders, multivariate regression analysis was performed using the results of the questionnaire surveys and equilibrium tests; including stabilometry, and caloric, vestibular evoked myogenic response, and head-up tilt tests.

RESULTS

Thirty-eight outpatients were included in this study, of which 14 patients (3 men, 11 women; mean age, 63.5 ± 15.9 years) received treatment without HBT, and 24 (1 man, 23 women; mean age, 58.2 ± 18.7 years) received combination treatment with HBT. Following HBT treatment, NPQ scores decreased significantly (baseline 40.1 ± 10.0 vs 2 mo 24.6 ± 17.7, P < 0.001). No statistically significant changes were observed in the NPQ scores in the non-HBT group (baseline 38.6 ± 12.2 vs 2 mo 39.4 ± 14.4, P = 0.92). Multivariable regression analysis revealed that the results of stabilometry (P = 0.02) and the caloric (P = 0.03), and head-up tilt tests (P < 0.001), HADS (P = 0.003), and PSQI (P = 0.01) were associated with HBT responsiveness in PPPD patients.

CONCLUSION

HBT may be an effective adjunct therapy for PPPD. Patients with autonomic dysfunction, unstable balance, semicircular canal paresis, anxiety, and poor sleep quality may be high responders to HBT.

Dietary intake of GDF11 delays the onset of several biomarkers of aging in male mice through anti-oxidant system via Smad2/3 pathway

Current studies have generated controversy over the age-related change in concentration of growth differentiation factor 11 (GDF11) and its role in the genesis of rejuvenation conditions. In this study, we displayed rGDF11 on the surface of Yarrowic Lipolytica (Y. lipolytica), and proved the bioavailability of the yeast-displayed rGDF11 by oral delivery in aged male mice. On the basis of these findings, we started to explore the anti-aging activity and underlying mechanisms of displayed rGDF11. It was found that dietary intake of displayed rGDF11 had little influence on the body weight and biochemical parameters of aged male mice, but delayed the occurrence and development of age-related biomarkers such as lipofuscin (LF) and senescence-associated-β-galactosidase, and to some extent, prolonged the lifespan of aged male mice. Moreover, we demonstrated once again that dietary intake of displayed rGDF11 enhanced the activity of anti-oxidant enzymes, including catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPX), reduced the reactive oxygen species (ROS) level, and slowed down the protein oxidation and lipid peroxidation. Importantly, we showed for the first time that rGDF11 enhanced the activity of CAT, SOD and GPX through activation of the Smad2/3 signaling pathway. Our study also provided a simple and safe route for delivery of recombinant GDF11, facilitating its therapeutic application in the future.

Survey of problems in Kampo curriculum and the need for interdisciplinary collaboration education in Japanese medical, pharmacy, dental, and nursing departments

In recent years, there has been a lot of research on the effectiveness of Kampo medicine. New findings from modern medicine are also being delivered in addition to traditional education in Japanese University. Kampo treatment covers a wide range of disorders. To achieve multidisciplinary cooperation in Kampo treatment, it is necessary to have an education system in which pharmacy, nursing, medicine and dentistry collaborate. The purpose of this study was to investigate the current status of Kampo classes in Japanese universities to clarify the problems experienced by each department and the needs for a system of interdisciplinary collaboration, and to examine what a new curriculum should encompass. We conducted a questionnaire survey of the Kampo curriculum at all medical, pharmaceutical, dental and nursing schools at universities in Japan. The target respondents were faculty members and administrators in charge of Kampo lectures. Multivariate analysis and correspondence analysis were conducted for multiple response items. Fisher's exact test and Cochrane's Q test were used to compare response frequency among departments and desired collaborators in each faculty, respectively. The results showed that the lack of instructors and the number of hours in the curriculum were problems in the departments of medicine, dentistry, and nursing. Medical, nursing, and dental departments cited the lack of time in their curriculum as a problem. The departments of medicine and pharmacy wished to further incorporate experiential learning (active learning) and problem-based learning/tutorial teaching methods. Incorporating an interdisciplinary collaboration system in the Kampo curriculum was required by a large percentage of respondents from all four academic departments. We identified trends in the problems and needs of each individual department, and this has given us direction for the development of Kampo curriculum in the future. Based on these findings, a new curriculum that includes interdisciplinary collaboration is required.

Decline in Liver Mitochondria Metabolic Function Is Restored by Hochuekkito Through Sirtuin 1 in Aged Mice With Malnutrition

Malnutrition impairs basic daily activities and leads to physical frailty, which is aggravated in the elderly compared with young adults. It is also well-known that the elderly are more vulnerable to metabolic stress. Therefore, in this study, using a food restricted (FR) mouse, we aimed to evaluate the effect of aging on locomotor activity and liver metabolic function. Further, we also investigated the involvement of hepatic mitochondria in liver metabolic function during aging, as well as the therapeutic benefit of the traditional Japanese medicine, hochuekkito (HET). Our findings indicated that following food restriction provided as 30% of ad libitum intake for 5 days, the locomotor activity was lower in 23–26-month-old (aged) mice than in 9-week-old (young) mice. Further, compared with young mice, aged mice exhibited significant decreases in the levels of metabolites related to the urea cycle, mitochondrial function, and anti-oxidative stress. The livers of the aged mice also showed a greater decrease in mitochondrial DNA copy number than young mice. Furthermore, the gene expression levels of sirtuin 1 (SIRT1) and mitochondrial biogenesis-related regulators were attenuated in aged mice. However, these changes were partially restored by HET treatment, which also improved locomotor activity, and combined treatment with alanine resulted in more significant effects in this regard. Therefore, our findings suggested that the decrease in locomotor activity in aged FR mice was associated with a decline in the metabolic function of hepatic mitochondria via decreased SIRT1 expression, which was restored by HET treatment. This implies that enhancing the metabolic function of liver mitochondria can contribute to alleviating energy deficiency in the elderly.

Advances in the Development of Nonpeptide Small Molecules Targeting Ghrelin Receptor

Ghrelin is an octanoylated peptide acting by the activation of the growth hormone secretagogue receptor, namely, GHS-R1a. The involvement of ghrelin in several physiological processes, including stimulation of food intake, gastric emptying, body energy balance, glucose homeostasis, reduction of insulin secretion, and lipogenesis validates the considerable interest in GHS-R1a as a promising target for the treatment of numerous disorders. Over the years, several GHS-R1a ligands have been identified and some of them have been extensively studied in clinical trials. The recently resolved structures of GHS-R1a bound to ghrelin or potent ligands have provided useful information for the design of new GHS-R1a drugs. This perspective is focused on the development of recent nonpeptide small molecules acting as GHS-R1a agonists, antagonists, and inverse agonists, bearing classical or new molecular scaffolds, as well as on radiolabeled GHS-R1a ligands developed for imaging. Moreover, the pharmacological effects of the most studied ligands have been discussed.

Ghrelin mediated hippocampal neurogenesis

The stomach hormone, ghrelin, which is released during food restriction, provides a link between circulating energy state and adaptive brain function. The maintenance of such homeostatic systems is essential for an organism to survive and thrive, and accumulating evidence points to ghrelin being a key regulator of adult hippocampal neurogenesis and memory function. Aberrant neurogenesis is linked to cognitive decline in aging and neurodegeneration. Therefore, identifying endogenous metabolic factors that regulate new adult-born neuron formation is an important objective in understanding the link between nutritional status and CNS function. Here, we review current developments in our understanding of ghrelin's role in regulating neurogenesis and memory function.

Kampo medicine for the holistic approach to older adults with heart failure

Heart failure (HF) is a leading cause of hospitalization, morbidity, and mortality in older adults and represents a significant clinical and economic burden on the health care system. However, there are many challenges in assessing and managing HF in elderly patients, who often have coexisting multimorbidity, frailty, and malnutrition. Therefore, it is often difficult to solve these problems with Western medicine alone, and a holistic approach, including Kampo medicine, can be helpful. In particular, managing volume control and frailty by adding Kampo formulas may help improve health-related quality of life and substantially impact prognosis in HF. This review article summarizes the role of Kampo medicine for older patients with HF and frailty.

Ghrelin Enhancer, the Latest Evidence of Rikkunshito

Rikkunshito is a Japanese herbal medicine (Kampo) that has been attracting attention and researched by many researchers not only in Japan but also worldwide. There are 214 rikkunshito articles that can be searched on PubMed by August 2021. The reason why rikkunshito has attracted so much attention is due to an epoch-making report (Gastroenterology, 2008) discovered that rikkunshito promotes the secretion of the orexigenic peptide ghrelin. Since then, many researchers have discovered that rikkunshito has a direct effect on the ghrelin receptor, GHS-R1a, and an effect of enhancing the ghrelin signal to the brain. Additionally, a lot of evidence that rikkunshito is expected to be effective for various gastrointestinal diseases have also been demonstrated. Numerous basic and clinical studies have suggested that rikkunshito affects (i) various discomforts caused by anticancer drugs, gastroesophageal reflux disease, functional dyspepsia, (ii) various stress-induced anorexia, (iii) hypophagia in the elderly, and (iv) healthy lifespan. In this review, as one who discovered the ghrelin enhancer effect of rikkunshito, we will review the research of rikkunshito so far and report on the latest research results.

Application of Kampo medicines for the palliation of cancer cachexia

Cancer cachexia results in the discontinuation of aggressive cancer therapy, and halting its progression has a significant effect on the survival rate and quality of life of patients with cancer. Currently, there are few therapies to control or slow down the progression of cancer cachexia. Although traditional Japanese Kampo medicine is widely used to support aggressive cancer therapy, the relevant scientific evidence is limited. Additionally, Kampo medicines are based on historical experience. In recent years, there have been widespread attempts to prove the efficacy of Kampo medicines through basic research, and an increasing number of studies have clarified the mechanism of action of Kampo medicines at the molecular level. It has been proposed that the improvement of cancer cachexia by Kampo medicines might involve enhancement of feeding via the central nervous system, improvement of protein maintenance in the skeletal muscle, and suppression of inflammatory cytokine production. In particular, among Kampo medicines, tonifying formulae, called "hozai" in Japanese, have been shown to be effective in alleviating cancer cachexia. In this review, we summarize the recent progress of basic and clinical research in Kampo medicines on cancer cachexia, and introduce Kampo medicines that are expected to be attractive supportive cancer medication.

Genus Sapium (Euphorbiaceae): A review on traditional uses, phytochemistry, and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Genus Sapium, belonging to Euphorbiaceae family, has a wide distribution in Asia and in temperate and tropical regions of Africa and America. The various parts of Sapium species have been used in traditional Chinese herbal medicine for the treatment of edema, skin-related diseases, bacterial infections, cancers, diabetes, and other ailments.

AIM OF THE STUDY

A comprehensive and updated review on the phytochemistry, pharmacology, and traditional medicinal uses of Sapium has been summarized and discussed to facilitate further exploitation of the therapeutic values of Sapium species.

MATERIALS AND METHODS

The relevant information of Sapium species was collected by scientific search engines including Elsevier, Google Scholar, Scifinder, and CNKI (China national knowledge infrastructure), and Master's dissertations and Summon from Shandong University Library.

RESULTS

Phytochemical studies revealed that approximately 259 compounds including terpenoids, phenylpropanoids, flavonoids, tannins, steroids, alkaloids, etc. have been isolated and identified from Sapium species, among which terpenoids, phenylpropanoids and tannins are the main constituents. Pharmacological in vitro and in vivo studies revealed that the extracts and pure compounds possessed significant antibacterial, antiinflammatory, antioxidant, antihypertensive effects, cytotoxicity, antidiabetic, molluscicidal effects. Terpenoids, phenylpropanoids, tannins, flavonoids, and alkaloids may be responsible for these activities.

CONCLUSIONS

The traditional uses, phytochemistry, and pharmacology described in this article demonstrated that the plants of Sapium genus possess many different types of compounds exhibiting wide range of biological activities, and they have high medicinal value and potential in the treatment of a variety of diseases. Detailed phytochemical studies have been conducted on only twelve species in the literature. More wide-ranging studies are still needed to explore this genus. Most of the existing bioactivity-related studies were implemented on crude extracts. More in-depth studies are necessary to reveal the links between the traditional uses and bioactivity in the future.

Identification of a Putative β-Arrestin Superagonist of the Growth Hormone Secretagogue Receptor (GHSR)

Ghrelin is a pleiotropic feeding hormone which also has a pivotal role in the central nervous system. Upon the activation of its receptor, growth hormone secretagogue receptor (GHSR), the Gα_q/11 -mediated and the β-arrestin-mediated signaling pathways are activated. As the β-arrestin pathway is a potential drug target, there is a strong need for β-arrestin-biased GHSR modulators. Activation of the β-arrestin pathway should inhibit the Gα_q/11 -mediated calcium flux through internalization of the receptor. Hence, we used the antagonistic activity in the calcium assay as the first screening for the β-arrestin activation. By conducting the second screening assay for the β-arrestin activation based on extracellular signal regulated kinase (ERK) 1/2 phosphorylation, we discovered a putative β-arrestin-biased superagonist. The activity of the compound was not completely blocked with the competitive antagonist, which implies that the effect is mediated, at least partly, by allosteric binding of the compound.

The role of central corticotrophin-releasing factor receptor signalling in plasma glucose maintenance through ghrelin secretion in calorie-restricted mice

Under severe calorie restriction (CR), the ghrelin-growth hormone axis in mice is involved in the maintenance of plasma glucose levels. Ghrelin, a stomach-derived acylated peptide, is up-regulated by the sympathetic nerve in the negative energy status. Central corticotrophin-releasing factor receptor (CRF-R) signalling stimulates the sympathetic tone. The present study aimed to examine the effect of central CRF-R signalling on the maintenance of plasma glucose concentrations in severe calorie-restricted mice with the involvement of ghrelin. Intracerebroventricular injections of urocorin-1 and urocorin-2, which are natural ligands for CRF-R1 and CRF-R2, elevated plasma ghrelin concentrations and ghrelin elevation with an i.c.v. injection of urocorin-1 was cancelled by atenolol (β1 adrenergic receptor antagonist) administration. We then established a mice model of 60% CR and found that the administration of [d-Lys3]-GHRP-6 (a ghrelin receptor antagonist) in mice under 60% CR reduced the plasma glucose concentration more compared to the vehicle mice. Similarly, the atenolol injection in mice under 60% CR significantly reduced the plasma glucose concentration, which was rescued by the co-administration of ghrelin. An i.c.v. injection of the alpha helical CRH, a non-selective corticotrophin-releasing factor receptor antagonist, in mice under 60% CR significantly reduced the plasma glucose concentration, although the co-administration of α-helical CRH with ghrelin maintained plasma glucose levels. These results suggest that central CRF-R signalling is involved in the maintenance of plasma glucose levels in mice under severe CR via the sympathetic-ghrelin pathway.

Acylated ghrelin protects against doxorubicin-induced nephropathy by activating silent information regulator 1

This study investigated the nephroprotective role of acylated ghrelin (AG) against DOX-induced nephropathy and examined whether the protection involves silent information regulator 1 (SIRT1). Rats were divided into control, control + AG, DOX, DOX + AG, DOX + AG + [D-Lys3]-GHRP-6 (a ghrelin receptor antagonist), and DOX + AG + EX-527 (a sirt1 inhibitor). DOX was given over the first 2 weeks. AG (10 ng/kg) and both inhibitors were given as 3 doses/wk for 5 weeks. AG improved the structure and the function of the kidneys; down-regulated the renal expression of TGF-β1, collagen 1A1 and α-SMA; and inhibited the renal collagen deposition in the kidneys of DOX-treated rats. Concomitantly, it reduced the renal levels of ROS, MDA, TNF-α, and IL-6 and protein levels of cytochrome-c, TGF-β1, Smad3 and α-SMA in these rats. In both the control and DOX-treated rats, AG significantly increased the renal levels of SOD and GSH, decreased the expression of cleaved caspase-3 and Bax, increased the total levels and the nuclear activity of SIRT1 and reduced the deacetylation of p53, NF-κB and FOXO-31. All the effects were abolished by the concurrent administration of EX-527 and [D-Lys3]-GHRP-6. In conclusion, AG prevents DOX-induced nephropathy in SIRT1 and GSHRa1-dependent mechanism.

Regulatory effects of ghrelin on endoplasmic reticulum stress, oxidative stress, and autophagy: Therapeutic potential

Ghrelin is a regulatory peptide that is the endogenous ligand of the growth hormone secretagogue 1a (GHS-R1a) which belongs to the G protein-coupled receptor family. Ghrelin and GHS-R1a are widely expressed in the central and peripheral tissues and play therapeutic potential roles in the cytoprotection of many internal organs. Endoplasmic reticulum stress (ERS), oxidative stress, and autophagy dysfunction, which are involved in various diseases. In recent years, accumulating evidence has suggested that ghrelin exerts protective effects by regulating ERS, oxidative stress, and autophagy in diverse diseases. This review article summarizes information about the roles of the ghrelin system on ERS, oxidative stress, and autophagy in multiple diseases. It is suggested that ghrelin positively affects the treatment of diseases and may be considered as a therapeutic drug in many illnesses.

Quercetin improves cognitive disorder in aging mice by inhibiting NLRP3 inflammasome activation

Quercetin is one of the most abundant dietary flavonoid compounds, and its mechanism for combating age-related neurodegenerative diseases is unclear. In this study, quercetin (35 and 70 mg kg^-1, orally administered for 4 weeks) was administered to 7-month-old aging mice (senescence-accelerated mouse prone 8 mice). As a result, it was found that quercetin could improve spatial learning and memory impairment displayed by aging mice in the Morris water maze. The results of immunoblotting reflected the protein expressions of the longevity factor (sirtuin1), inflammasomes (NLRP3 and ASC), synaptic marker (PSD95) and neurotrophic factors (BDNF and NGF) in the hippocampus of the brain. It indicated that the intervention of quercetin could increase the expression of sirtuin1 and prevent neuroinflammation, which was evident from the decrease in the protein levels of the astrocyte marker (GFAP) and inflammatory factors (cleaved-caspase 1, IL-1β and IL-18). In addition, quercetin could reduce the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) in the hippocampus of aging mice. Current data indicated that quercetin might improve neuroinflammation in aging mice by regulating the Sirtuin1/NLRP3 pathway.

Hydrogen Sulfide and Carnosine: Modulation of Oxidative Stress and Inflammation in Kidney and Brain Axis

Emerging evidence indicates that the dysregulation of cellular redox homeostasis and chronic inflammatory processes are implicated in the pathogenesis of kidney and brain disorders. In this light, endogenous dipeptide carnosine (β-alanyl-L-histidine) and hydrogen sulfide (H₂S) exert cytoprotective actions through the modulation of redox-dependent resilience pathways during oxidative stress and inflammation. Several recent studies have elucidated a functional crosstalk occurring between kidney and the brain. The pathophysiological link of this crosstalk is represented by oxidative stress and inflammatory processes which contribute to the high prevalence of neuropsychiatric disorders, cognitive impairment, and dementia during the natural history of chronic kidney disease. Herein, we provide an overview of the main pathophysiological mechanisms related to high levels of pro-inflammatory cytokines, including interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and neurotoxins, which play a critical role in the kidney–brain crosstalk. The present paper also explores the respective role of H₂S and carnosine in the modulation of oxidative stress and inflammation in the kidney–brain axis. It suggests that these activities are likely mediated, at least in part, via hormetic processes, involving Nrf2 (Nuclear factor-like 2), Hsp 70 (heat shock protein 70), SIRT-1 (Sirtuin-1), Trx (Thioredoxin), and the glutathione system. Metabolic interactions at the kidney and brain axis level operate in controlling and reducing oxidant-induced inflammatory damage and therefore, can be a promising potential therapeutic target to reduce the severity of renal and brain injuries in humans.

Acylated Ghrelin as a Multi-Targeted Therapy for Alzheimer's and Parkinson's Disease

Much thought has been given to the impact of Amyloid Beta, Tau and Alpha-Synuclein in the development of Alzheimer's disease (AD) and Parkinson's disease (PD), yet the clinical failures of the recent decades indicate that there are further pathological mechanisms at work. Indeed, besides amyloids, AD and PD are characterized by the culminative interplay of oxidative stress, mitochondrial dysfunction and hyperfission, defective autophagy and mitophagy, systemic inflammation, BBB and vascular damage, demyelination, cerebral insulin resistance, the loss of dopamine production in PD, impaired neurogenesis and, of course, widespread axonal, synaptic and neuronal degeneration that leads to cognitive and motor impediments. Interestingly, the acylated form of the hormone ghrelin has shown the potential to ameliorate the latter pathologic changes, although some studies indicate a few complications that need to be considered in the long-term administration of the hormone. As such, this review will illustrate the wide-ranging neuroprotective properties of acylated ghrelin and critically evaluate the hormone's therapeutic benefits for the treatment of AD and PD.

High-protein and low-calorie diets improved the anti-aging Klotho protein in the rats' brain: the toxic role of high-fat diet

BACKGROUND

In the current study, our specific aim was to characterize the Klotho protein and expression levels in the hippocampus and prefrontal cortex of old rats treated with different diets (high-fat, high-protein, low-calorie, high-protein and low-calorie).

METHODS

Rats were treated with high-fat, high-protein, low-calorie, low-calorie high-protein diets for 10 weeks and then behavioral and molecular assessments were evaluated.

RESULTS

Statistical analysis showed the percentage of open arm time was increased in the high-protein, low-calorie and low-calorie high-protein groups compared with old control (old-C) rats. The percentage of open arm entries was increased in the low-calorie and low-calorie high-protein group compared with old-C rats. The body weight and serum triglyceride were decreased in the low-calorie and low-calorie high-protein groups in comparison to control old rats. Low-calorie and low-calorie high-protein treatments statistically enhanced caspase-3 level compared with old-C rats in the hippocampus and prefrontal cortex. Treatment of old rats with high-protein, low-calorie and low-calorie high-protein could increase Klotho-α level compared with control old rats. The levels of Klotho-α, c-fos and brain-derived neurotrophic factors were decreased in the low-calorie high-protein group in Klotho inhibitor's presence compared with the low-calorie high-protein group.

CONCLUSION

According to our findings, Klotho-α level was reduced in old rats. Low-calorie, high-protein and particularly low-calorie high-protein diets increased this protein level and consequently increased neuronal plasticity and improved memory function.

GRAPHIC ABSTRACT

Heal the heart through gut (hormone) ghrelin: a potential player to combat heart failure

Ghrelin, a small peptide hormone (28 aa), secreted mainly by X/A-like cells of gastric mucosa, is also locally produced in cardiomyocytes. Being an orexigenic factor (appetite stimulant), it promotes release of growth hormone (GH) and exerts diverse physiological functions, viz. regulation of energy balance, glucose, and/or fat metabolism for body weight maintenance. Interestingly, administration of exogenous ghrelin significantly improves cardiac functions in CVD patients as well as experimental animal models of heart failure. Ghrelin ameliorates pathophysiological condition of the heart in myocardial infarction, cardiac hypertrophy, fibrosis, cachexia, and ischemia reperfusion injury. This peptide also exerts significant impact at the level of vasculature leading to lowering high blood pressure and reversal of endothelial dysfunction and atherosclerosis. However, the molecular mechanism of actions elucidating the healing effects of ghrelin on the cardiovascular system is still a matter of conjecture. Some experimental data indicate its beneficial effects via complex cellular cross talks between autonomic nervous system and cardiovascular cells, some other suggest more direct receptor-mediated molecular actions via autophagy or ionotropic regulation and interfering with apoptotic and inflammatory pathways of cardiomyocytes and vascular endothelial cells. Here, in this review, we summarise available recent data to encourage more research to find the missing links of unknown ghrelin receptor-mediated pathways as we see ghrelin as a future novel therapy in cardiovascular protection.

Novel in vivo and in vitro mechanisms of positive inotropic effect of atractylodin

This study was to investigate the inotropic effect of atractylodin and its underlying mechanism. The cardiac pressure-volume loop (P-V loop), Langendroff-perfused isolated rat heart, patch-clamp, Ca²⁺ transient and western blot techniques were used. The results demonstrated that atractylodin (3 mg/kg, ip) remarkably increased the left ventricular stroke work, cardiac output, stroke volume, heart rate, ejection fraction, end-systolic pressure, peak rates of rise and fall of left ventricular pressures (+dP/dt_max , -dP/dt_max ), the slopes of end-systolic pressure-volume relationship (also named as end-systolic elastance, Ees) and reducing end-systolic volume and end-diastolic volume in the in vivo rat study. Also, atractylodin (3 mg/kg, ip) significantly decreased diastolic blood pressure and the arterial elastance (Ea) without significant systolic blood pressure change. In addition, atractylodin (0.1, 1, 10 µmol/L) also increased the isolated rat heart left ventricular developed pressure which is the difference between the systolic and diastolic pressure in non-pacing and pacing modes. Furthermore, JMV-2959 (1 μmol/L), a ghrelin receptor unbiased antagonist, blocked the increased left ventricular developed pressure of atractylodin in isolated rat hearts. Finally, atractylodin (5 µmol/L) increased the amplitude of Ca²⁺ transient by enhancing SERCA2a activity, the sarcoplasmic reticulum Ca²⁺ content and the phosphorylation of phospholamban at 16-serine. These results demonstrated that atractylodin had a positive inotropic effect by enhancing SERCA2a activity which might be mediated by acting ghrelin receptor in myocardium. In conclusion, atractylodin which had the positive inotropic effect and decreased diastolic blood pressure might serve as an agent for the treatment of heart failure in clinical settings.

Ghrelin/GHS-R1a signaling plays different roles in anxiety-related behaviors after acute and chronic caloric restriction

The brain-gut hormone ghrelin and its receptor GHS-R1a, the growth hormone secretagogue receptor 1a, regulates diverse functions of central nervous system including stress response and mood. Both acute and chronic caloric restrictions (CR) were reported to increase endogenous ghrelin level meanwhile regulate anxiety-related behaviors; however, the causal relationship between CR-induced ghrelin elevation and anxiety are not fully established. Here, we introduced an acute (24 h) and a chronic (10wks) CR procedure to both GHS-R1a KO (Ghsr^-/-) mice and WT (Ghsr^+/+) littermates, and compared their anxiety-related behaviors. We found that acute CR induced anxiolytic and anti-despairing behaviors in Ghsr^+/+ mice but not in Ghsr^-/- mice. Ad-libitum refeeding abolished the effect of acute CR on anxiety-related behaviors. In contrast, chronic CR for 10wks facilitated despair-like behavior meanwhile inhibited anxiety-like behavior in Ghsr^+/+ mice. GHS-R1a deficiency rescued despair-like behavior while did not affect anxiolytic response induced by chronic CR. In addition, we found elevated interleukin-6 (IL-6) in serum of Ghsr^+/+ mice after chronic CR, but not in Ghsr^-/- mice. Altogether, our findings indicated that acute CR and chronic CR have different impacts on anxiety-related behaviors, and the former is dependent on ghrelin/GHS-R1a signaling while the latter may not always be. In addition, our findings suggested that GHS-R1a-dependent elevation in serum IL-6 might contribute to increased despair-like behavior in chronic CR state.

Vulnerability to psychological stress-induced anorexia in female mice depends on blockade of ghrelin signal in nucleus tractus solitarius

Background and Purpose

Women have a higher incidence of eating disorders than men. We investigated whether the effects of ghrelin on feeding are affected by sex and stress, and to elucidate the mechanisms that may cause sex differences in stress‐mediated anorexia, focusing on ghrelin.

Experimental Approach

Acylated ghrelin was administered to naïve and psychologically stressed male and female C57BL/6J mice, followed by measurements of food intake and plasma hormone levels. Ovariectomy was performed to determine the effects of ovary‐derived oestrogen on stress‐induced eating disorders in female mice. The numbers of Agrp or c‐Fos mRNA‐positive cells and estrogen receptor α/c‐Fos protein‐double‐positive cells were assessed.

Key Results

Ghrelin administration to naïve female mice caused a higher increase in food intake, growth hormone secretion, Agrp mRNA expression in the arcuate nucleus and c‐Fos expression in the nucleus tractus solitarius (NTS) than in male mice. In contrast, psychological stress caused a more sustained reduction in food intake in females than males. The high sensitivity of naïve females to exogenous ghrelin was attenuated by stress exposure. The stress‐induced decline in food intake was not abolished by ovariectomy. Estrogen receptor‐α but not ‐β antagonism prevented the decrease in food intake under stress. Estrogen receptor‐α/c‐Fos‐double‐positive cells in the NTS were significantly increased by stress only in females.

Conclusion and Implications

Stress‐mediated eating disorders in females may be due to blockade of ghrelin signalling via estrogen receptor‐α activation in the NTS. Targeting the ghrelin signal in the brain could be a new treatment strategy to prevent these disorders.

Developmental stage-dependent relationships between ghrelin levels and hippocampal white matter connections in low-weight anorexia nervosa and atypical anorexia nervosa

INTRODUCTION

Disruptions in homeostatic and hedonic food motivation are proposed to underlie anorexia nervosa (AN) and atypical AN, restrictive eating disorders which commonly onset in puberty. Ghrelin, a neuroprotective hormone that drives hedonic eating is increased in AN and is expressed in the hippocampus. White matter (WM) undergoes significant change during puberty in regions involved in food motivation, particularly WM tracts connected with the hippocampus. The association between ghrelin and WM region of interest (ROI) with hippocampal connections in restrictive eating disorders, particularly in adolescence during key neurodevelopmental growth, is unknown.

METHODS

We evaluated fasting plasma ghrelin and WM microstructure (measured by free-water corrected fractional anisotropy (FA-t)) in WM ROIs with hippocampal connections - the fornix and the hippocampal portion of the cingulum - in 56 adolescent females (age range: 11.9 - 22.1 y; mean: 19.0 y) with low-weight eating disorders including AN and atypical AN (N = 36) and healthy controls (N = 20).

RESULTS

FA-t in the fornix or hippocampal portion of the fornix did not differ between groups. Ghrelin was higher in AN/atypical AN vs. HC and was positively correlated with puberty stage in the AN/atypical AN group, but not the HC group. The correlation between ghrelin and FA-t in the fornix was significantly different in females with AN/atypical AN compared to controls. In AN/atypical AN, pubertal stage moderated the relation between fasting plasma ghrelin and FA-t in the fornix: higher fasting ghrelin was associated with lower FA-t in the fornix in late-post-puberty, but was not associated with FA-t in the early to mid stages of puberty.

CONCLUSIONS

In post-pubertal females with low-weight AN/atypical AN, higher levels of ghrelin are associated with lower FA-t in the fornix. This relationship is not evident in the early to mid stages of puberty in AN/atypical AN or in HC, and may reflect a lack of possible neuroprotective effects of ghrelin in late-post puberty only. Understanding the effects of ghrelin on WM microstructure longitudinally and following recovery from AN/Atypical AN and how this differs across pubertal stages will be an important next step. These findings could ultimately inform treatment staging and aid in diagnosis and detection of AN/atypical AN.

Selective neuronal vulnerability in Alzheimer's disease

Alzheimer's disease (AD) is defined by a deficiency in specific behavioural and/or cognitive domains, pointing to selective vulnerabilities of specific neurons from different brain regions. These vulnerabilities can be compared across neuron subgroups to identify the most vulnerable neuronal types, regions, and time points for further investigation. Thus, the relevant organizational frameworks for brain subgroups will hold great values for a clear understanding of the progression in AD. Presently, the neuronal vulnerability has yet urgently required to be elucidated as not yet been clearly defined. It is suggested that cell-autonomous and non-cell-autonomous mechanisms can affect the neuronal vulnerability to stressors, and in turn modulates AD progression. This review examines cell-autonomous and non-cell-autonomous mechanisms that contribute to the neuronal vulnerability. Collectively, the cell-autonomous mechanisms seem to be the primary drivers responsible for initiating specific stressor-related neuronal vulnerability with pathological changes in certain brain areas, which then utilize non-cell-autonomous mechanisms and result in subsequent progression of AD. In summary, this article has provided a new perspective on the preventative and therapeutic options for AD.

Omics biomarkers for frailty in older adults

Frailty is a clinical state characterized by an age-related unsteady state of the body, a decline in physiological function, and an increased vulnerability to adverse outcomes. Early diagnosis of frailty is important for improving the quality of life in older adults and promoting healthy aging. The biological mechanisms underlying frailty have been extensively studied in recent years. Combining assessment tools and biomarkers can facilitate the early diagnosis of frailty. However, there is a lack of stable and reliable frailty-related biomarkers for use in clinical practice. Advances in the multi-omics platforms have provided new information on the molecular mechanisms underlying frailty. Thus, identifying biomarkers using omics-based approaches helps explore the physiological mechanisms underlying frailty, and aids the evaluation of the risk of frailty development and progression. This article reviews the current status of frailty biomarkers from the genomics, transcriptomics, proteomics, and metabolomics perspectives.

A traditional herbal medicine rikkunshito prevents angiotensin II-Induced atrial fibrosis and fibrillation

BACKGROUND

Rikkunshito (RKT), a traditional herbal medicine, has been demonstrated to exert anti-inflammatory, anti-apoptotic, and anti-fibrotic effects in several organs. This study tested the hypothesis that RKT can suppress angiotensin II (AngII)-induced inflammatory atrial fibrosis and ameliorate enhanced vulnerability to atrial fibrillation (AF).

METHODS

Eight-week-old male C57BL/6 mice were subcutaneously infused with either vehicle or AngII (2.0 mg/kg/day) for 2 weeks. Water or RKT at a dose of 1000 mg/kg/day were orally administered once daily for 2 weeks. Morphological, histological, and biochemical analyses were performed. AF was induced either by transesophageal burst pacing in vivo or by burst/extrastimuli in isolated perfused hearts using a Langendorff apparatus.

RESULTS

RKT at a dose of 1000 mg/kg/day for 2 weeks attenuated atrial interstitial fibrosis and profibrotic and proinflammatory signals induced by continuous infusion of AngII. RKT attenuated AngII-induced enhanced vulnerability to AF in in vivo experiments and in isolated perfused hearts. Atractylodin, an active component of RKT, exhibited antifibrotic activity comparable to that of RKT. RKT reversed AngII-induced suppression of sirtuin 1 (Sirt1) translocation to the nuclei. RKT suppressed AngII-induced phosphorylation of IκB, overexpression of p53, and cellular apoptotic signals and apoptosis. All of the antagonizing effects of RKT against AngII were attenuated by a concomitant treatment with a growth hormone secretagogue receptor (GHSR)-inhibitor.

CONCLUSION

Our results demonstrated that RKT prevented atrial fibrosis and attenuated enhanced vulnerability to AF induced by AngII. The results also suggested that potentiating the GHSR-Sirt1 pathway is involved in these processes.

Phytotherapy for Cachexia: Where Do We Stand?

Background

In contrast to Western medicine which currently offers no approved pharmacotherapy options for cachexia, in Japan multi-component extracts of medicinal plants are used with coverage by the national health insurance. This so called “Kampo” medicine is an example of the modern concept of multi-component/multi-target therapy. For the three traditional preparations Hochuekkito (補中益気湯), Juzentaihoto (十全大補湯), and Rikkunshito (六君子湯), a multitude of clinical research data relating to cachexia has been published. These preparations are also referred to as “Hozai” (補剤). A similar concept is found in Russian herbal medicine, where the term “Adaptogen” was coined for pharmacologically active substances which enhance adaptive stress repose.

Methods

Scientific literature—including original Japanese articles—was reviewed regarding the effects of these herbal preparations on cachexia. Cachexia is a complex set of symptoms including muscle atrophy with loss of weight, fatigue, and weakness.

Results

In a 1985 study by Kuroda et al., Hochuekkito showed efficacy in involuntary weight loss and fatigue in 63% of 162 patients with genitourinary cancer. For cancer-related fatigue, a significant improvement was reported within 2 weeks by Jeong et al. in 2010. In patients with chronic fatigue syndrome, Hochuekkito showed an overall improvement with 8–12 weeks of therapy in a 1997 study by Kuratsune et al. In a 2005 randomized placebo-controlled trial by Satoh et al. on 13 geriatric Q1 patients in a 16-week treatment protocol, Hochuekkito showed significant improvement of general health, physical functioning and the Profile of Mood States (POMS). In 71 geriatric COPD patients in a 2009 placebo-controlled randomized study, Tatsumi et al. found a significant body weight increase and a CRP, TNF-α, IL-6 decrease over 6 months of therapy. For Juzentaihoto in 48 hepatocellular carcinoma patients, Tsuchiya et al. 2008 documented a significantly longer recurrence-free survival (49 vs. 24 months) as compared to the control group (p=0.023). For the much simpler Rikkunshito prescription, a 2011 retrospective study by Fujitsuka et al. on 39 Stage III/IV pancreatic cancer patients treated with Gemcitabine (n=33) or Gemcitabine/Rikkunshito (n=6) showed a significantly prolonged median survival with 224 vs. 378.5 days (p < 0.05). In a 2011 open-label clinical study by Utumi et al. on geriatric cachexia in 6 dementia patients, treatment with Rikkunshito for 4 weeks resulted in a significant body weight increase. In all the above studies, the standardized dosage of 3x2.5 g/d extract granules for most Japanese health insurance-covered Kampo extract-preparations was applied.

Conclusion

As there is currently no accepted pharmacotherapy option for cachexia available in the West, a transfer of these East Asian gold standard prescriptions into the European market would be desirable. We were further able to demonstrate that the mTOR, interleucin, and melatonin pathways are modified by herbal compounds which thus counteract cachexia. More research in this field is urgently needed in order to provide new, effective treatments for cachexia patients.

Sirtuin-1 regulates organismal growth by altering feeding behavior and intestinal morphology in planarians

Nutrient availability upon feeding leads to an increase in body size in the planarian Schmidtea mediterranea However, it remains unclear how food consumption integrates with cell division at the organismal level. Here, we show that the NAD-dependent protein deacetylases sirtuins are evolutionarily conserved in planarians, and specifically demonstrate that the homolog of human sirtuin-1 (SIRT1) (encoded by Smed-Sirt-1), regulates organismal growth by impairing both feeding behavior and intestinal morphology. Disruption of Smed-Sirt-1 with RNAi or pharmacological inhibition of Sirtuin-1 leads to reduced animal growth. Conversely, enhancement of Sirtuin-1 activity with resveratrol accelerates growth. Differences in growth rates were associated with changes in the amount of time taken to locate food and overall food consumption. Furthermore, Smed-Sirt-1(RNAi) animals displayed reduced cell death and increased stem cell proliferation accompanied by impaired expression of intestinal lineage progenitors and reduced branching of the gut. Taken together, our findings indicate that Sirtuin-1 is a crucial metabolic hub capable of controlling animal behavior, tissue renewal and morphogenesis of the adult intestine.

Rikkunshito attenuates induction of epithelial-mesenchymal switch via activation of Sirtuin1 in ovarian cancer cells

Rikkunshito, a traditional Japanese herbal medicine, improves appetite via activation of gastrointestinal hormone ghrelin pathway. The function of ghrelin is mediated by growth hormone secretagogue receptor (GHSR1a), and ghrelin has been known to possess diverse physiological functions including growth suppression of some cancer cells. Considering that increased ghrelin signaling by Rikkunshito could enhance sirtuin1 (SIRT1) activity in nervous system, we aimed to investigate the effect of Rikkunshito in ovarian cancer cells. Ovarian cancer cell lines were treated with Rikkunshito, and cellular viability, gene expressions and epithelial-mesenchymal transition (EMT) status were investigated. To investigate the involvement of SIRT1 by Rikkunshito in SKOV3 cancer cells, endogenous expression of SIRT1 was depleted using small interfering RNA (siRNA). Treatment with Rikkunshito elevated ghrelin, GHSR1a and SIRT1, while cellular viability was decreased. The treatment of Rikkunshito also inhibited cellular migration and invasion status in a dose-dependent manner, and these effects were translated to the enhanced EMT status, although the role of SIRT1 was not determined. Our study revealed a novel function of Rikkunshito in enhancing EMT status of ovarian cancer cells. Therefore, we would like to propose that Rikkunshito may be used as a novel adjunctive therapy in chemotherapy of ovarian cancer because platinum-based chemotherapy frequently used for the treatment of ovarian cancer inevitably impairs appetite.

Intermedin1-53 attenuates aging-associated vascular calcification in rats by upregulating sirtuin 1

Vascular calcification is a common phenomenon in older adults. Intermedin (IMD) is a cardiovascular bioactive peptide inhibiting vascular calcification. In this study, we aimed to investigate whether IMD_1-53 attenuates aging-associated vascular calcification. Vascular calcification was induced by vitamin D3 plus nicotine (VDN) in young and old rats. The calcification in aortas was more severe in old rats treated with VDN than young control rats, and IMD expression was lower. Exogenous administration of IMD_1-53 significantly inhibited the calcium deposition in aortas and the osteogenic transdifferentiation of vascular smooth muscle cells (VSMCs) in VDN-treated old rats. Moreover, levels of aging-related p16, p21 and β-galactosidase were all greatly decreased by IMD_1-53. These results were further confirmed in rat and human VSMCs in vitro. In addition, IMD-deficient mouse VSMCs showed senescence features coinciding with osteogenic transition as compared with wild-type mouse VSMCs. Mechanistically, IMD_1-53 significantly increased the expression of the anti-aging factor sirtuin 1 (sirt1); the inhibitory effects of IMD_1-53 on calcification and senescence were blocked by sirt1 knockdown. Furthermore, preincubation with inhibitors of PI3K, AMPK or PKA efficiently blunted the upregulatory effect of IMD_1-53 on sirt1. Consequently, IMD_1-53 could attenuate aging-associated vascular calcification by upregulating sirt1 via activating PI3K/Akt, AMPK and cAMP/PKA signaling.

Effects of Rikkunshito treatment on renal fibrosis/inflammation and body weight reduction in a unilateral ureteral obstruction model in mice

Chronic kidney disease (CKD) progresses to end-stage renal failure via renal tubulointerstitial fibrosis. Malnutrition, inflammation, and arteriosclerosis interact to exacerbate the poor prognosis of CKD, and their effective management is thus essential. The traditional Japanese medicine Rikkunshito (RKT) exerts appetite-stimulating effects via ghrelin, which attenuates inflammation and fibrosis. We evaluated the therapeutic effect of RKT in unilateral ureter obstruction (UUO)-induced renal fibrosis/inflammation and body weight loss in mice. UUO and sham-operated mice were fed a standard diet or diet containing 3.0% RKT. Renal fibrosis was investigated by histopathology and macrophage infiltration was determined by immunohistochemistry. Expression levels of genes associated with fibrosis, inflammation, ghrelin, and mitochondrial function were determined by quantitative reverse transcription-polymerase chain reaction and western blot analyses. RKT treatment partially prevented UUO-induced weight loss but failed to attenuate renal fibrosis and inflammation. Renal expression of sirtuin 1, a ghrelin-downstream signalling molecule, and gene expression of peroxisome proliferator-activated receptor-γ coactivator 1α and Bcl-2/adenovirus E1B interacting protein 3 were unaffected by RKT. These results indicate that RKT inhibits weight loss but does not improve renal fibrosis or inflammation in a rapidly progressive renal fibrosis mouse model. RKT may have a protective effect on weight loss associated with CKD.

Hydrogen Sulfide Inhibits Homocysteine-Induced Neuronal Senescence by Up-Regulation of SIRT1

Homocysteine (Hcy) accelerates neuronal senescence and induces age-related neurodegenerative diseases. Silence signal regulating factor 1 (SIRT1) prolongs lifespan and takes neuroprotective effects. We have previously demonstrated that hydrogen sulfide (H₂S) prevents Hcy-induced apoptosis of neuronal cells and has neuroprotective effect. In the present work, we aimed to investigate whether H₂S protects HT22 cells against Hcy-induced neuronal senescence and whether SIRT1 mediates this role of H₂S. We found that Hcy induced cellular senescence in HT22 cells, as determined by β-galactosidase staining, expressions of P16^INK4a, P21^CIPL, and trypan blue Staining, which are the markers of cellular senescence. However, sodium hydrosulfide (NaHS, the donor of H₂S) significantly reversed Hcy-induced cellular senescence. Interestingly, NaHS not only up-regulated the expression of SIRT1 in HT22 cells but also reversed Hcy-downregulated the expression of SIRT1 in HT22 cells. Furthermore, we found that pretreatment with Sirtinol (an inhibitor of SIRT1) markedly reversed the protection of NaHS against Hcy-induced HT22 cells senescence and apoptosis. Our findings illustrated that H₂S protects HT22 cells against Hcy-induced senescence by up-regulating SIRT1.

Effects of rikkunshito supplementation on resistance to oxidative stress and lifespan in mice

AIM

Caloric restriction (CR), which limits the caloric intake to 60-70% of ad libitum (AL) amounts in various experimental animals, delays aging and extends the lifespan. We previously showed that neuropeptide Y (NPY), an appetite-stimulating peptide, is essential for the anti-oxidative and life-extending effects of CR. Here, we investigated whether a Japanese traditional herbal medicine, rikkunshito (RKT), which induces NPY activation, has CR-like life-extending effects.

METHODS

First, we evaluated the life-extending activity of RKT by examining the effect of long-term RKT administration on wild-type and NPY knockout mice. Furthermore, we tested whether RKT enhances CR-mediated beneficial effects under AL conditions with a normal diet and under mild CR conditions with a high-fat diet. We then used 3-nitropropionic acid or doxorubicin to induce oxidative stress, and analyzed the differences in survival rate, weight loss, gene expression and cellular oxidative damage among groups.

RESULTS

RKT administration did not extend the lifespan of wild-type or NPY knockout mice. In the oxidative stress models, RKT treatment upregulated anti-oxidative gene expression in the liver. Furthermore, RKT administration reduced the oxidative damage in the liver compared to the CR conditions alone. However, on induction of oxidative stress by 3-nitropropionic acid or doxorubicin, RKT administration did not affect the survival rate.

CONCLUSIONS

These results show that RKT administration only partially mimics the effects of CR at the cellular level, but not at the organismal level to increase the lifespan of mice. Geriatr Gerontol Int 2019; ••: ••-••.

Cardiac ageing: extrinsic and intrinsic factors in cellular renewal and senescence

Cardiac ageing manifests as a decline in function leading to heart failure. At the cellular level, ageing entails decreased replicative capacity and dysregulation of cellular processes in myocardial and nonmyocyte cells. Various extrinsic parameters, such as lifestyle and environment, integrate important signalling pathways, such as those involving inflammation and oxidative stress, with intrinsic molecular mechanisms underlying resistance versus progression to cellular senescence. Mitigation of cardiac functional decline in an ageing organism requires the activation of enhanced maintenance and reparative capacity, thereby overcoming inherent endogenous limitations to retaining a youthful phenotype. Deciphering the molecular mechanisms underlying dysregulation of cellular function and renewal reveals potential interventional targets to attenuate degenerative processes at the cellular and systemic levels to improve quality of life for our ageing population. In this Review, we discuss the roles of extrinsic and intrinsic factors in cardiac ageing. Animal models of cardiac ageing are summarized, followed by an overview of the current and possible future treatments to mitigate the deleterious effects of cardiac ageing.

Antiinflammatory constituents of Atractylodes chinensis rhizome improve glomerular lesions in immunoglobulin A nephropathy model mice

The crude drug Sojutsu, as defined by the Japanese Pharmacopoeia, is the rhizome of Atractylodes lancea De Candolle, Atractylodes chinensis Koidzumi, or their interspecific hybrids (Asteraceae). Sojutsu is one of the traditional Kampo formulas, which are administered to patients suffering from stomach disorders, edema, and nephrotic syndrome. Although antiinflammatory effects of Sojutsu have been reported, its effects on the liver and kidney have not been extensively investigated. Here, we used a Sojutsu sample identified as A. chinensis rhizome and isolated several constituents from its ethyl acetate (EtOAc)-soluble fraction that decreased production of the proinflammatory mediator nitric oxide (NO) in interleukin 1β-treated rat hepatocytes. Among the constituents in this fraction, atractylodin showed the highest activity to suppress NO production, whereas hinesol, β-eudesmol, and α-bisabolol showed low activity. Atractylodin decreased the levels of inducible nitric oxide synthase, tumor necrosis factor α, and lipocalin 2 messenger RNAs (mRNAs). The EtOAc-soluble fraction of the A. chinensis rhizome extract was administered daily for 20 weeks to high immunoglobulin A (HIGA) mice, whose pathological findings resemble human immunoglobulin A nephropathy. This fraction decreased the weight of white adipose tissue and decreased mesangial proliferation and immunoglobulin A deposition in glomeruli. These results indicate that the EtOAc-soluble fraction, which included antiinflammatory constituents, may be responsible for improvement of the mesangial lesions in HIGA mice.

Mechanisms of Leptin and Ghrelin Action on Maturation and Functions of Dendritic Cells

Molecular mechanisms of the immunomodulatory effects of leptin and ghrelin in concentrations typical for pregnancy on the maturation and functional activity of dendritic cells (DCs) generated from the peripheral blood monocytes of women are investigated. The presence of leptin during DC maturation did not affect the levels of CD83⁺CD1c⁺, CD86⁺CD1c⁺, and HLA-DR⁺CD1c⁺ DCs, but increased the amount and the activity of the enzyme indoleamine 2,3-dioxygenase (IDO). Cell culturing in the presence of ghrelin or combination of leptin and ghrelin reduced the percentage of CD86⁺CD1c⁺ DCs but did not affect the levels of CD83⁺CD1c⁺ and HLA-DR⁺CD1c⁺ DCs. In addition, ghrelin reduced the number of IDO molecules without affecting its activity. Simultaneous presence of leptin and ghrelin increased induced IDO activity without affecting the amount of the enzyme in DCs. The effects of leptin and ghrelin on the investigated functions of DCs in some cases correlated with high levels of cAMP. New mechanisms for leptin and ghrelin regulation of tolerogenic functions of DCs in pregnancy are proposed.