PELI1 Selectively Targets Kinase-Active RIP3 for Ubiquitylation-Dependent Proteasomal Degradation.

Receptor-interacting protein kinase-3 (RIP3 or RIPK3) is a central protein in necroptosis, but posttranslational processes that regulate RIP3 activity and stability remain poorly understood. Here, we identify pellino E3 ubiquitin protein ligase 1 (PELI1) as an E3 ligase that targets RIP3 for proteasome-dependent degradation. Phosphorylation of RIP3 on T182 leads to interaction with the forkhead-associated (FHA) domain of PELI1 and PELI1-mediated K48-linked polyubiquitylation of RIP3 on K363. This same phosphorylation event is also important for RIP3 kinase activity; thus, PELI1 preferentially targets kinase-active RIP3 for degradation. PELI1-mediated RIP3 degradation effectively prevents cell death triggered by RIP3 hyperactivation. Importantly, upregulated RIP3 expression in keratinocytes from toxic epidermal necrolysis (TEN) patients is correlated with low expression of PELI1, suggesting that loss of PELI1 may play a role in the pathogenesis of TEN. We propose that PELI1 may function to control inadvertent activation of RIP3, thus preventing aberrant cell death and maintaining cellular homeostasis.

Dietary cholesterol intake is not associated with the development of chronic kidney disease: Results from two Korean cohort studies.

BACKGROUND AND AIMS: Although dyslipidemia is a major risk factor for chronic kidney disease (CKD), the relationship between dietary cholesterol and CKD remains unknown. We investigated the association between cholesterol intake and CKD risk. METHODS AND RESULTS: The Korea National Health and Nutrition Examination Survey (KNHANES) 2019-2021 (n = 13,769) and the Korean Genome and Epidemiology Study (KoGES) (n = 9225) data were used for this study. Cholesterol intake was assessed using a 24-h recall food frequency questionnaire, and participants were categorized into three groups (T1, T2, and T3) based on cholesterol intake. Primary outcomes were prevalence and incidence of CKD. Higher cholesterol intake was modestly associated with increased serum levels of total, low-density lipoprotein, and high-density lipoprotein cholesterol in the KNHANES. However, we found no significant association between cholesterol intake and CKD prevalence in the KNHANES, regardless of a history of hypercholesterolemia. In the KoGES, during a median follow-up of 11.4 years, cholesterol intake was not associated with incident CKD in participants without hypercholesterolemia (hazard ratio [HR] per 10 mg increase, 1.00; 95 % confidence interval [CI], 0.99-1.01) and in those with hypercholesterolemia (HR, 1.01; 95 % CI, 0.98-1.04). Egg consumption also showed no significant association with the risk of incident CKD. Additionally, cholesterol intake had no significant interaction on the relationships between serum cholesterol levels and incident CKD. CONCLUSION: Although cholesterol intake was associated with increased serum cholesterol levels, it was not associated with CKD prevalence and incidence. Our findings suggest that reducing cholesterol intake alone may not be sufficient to prevent CKD.

Relationship Between High-Density Lipoprotein Cholesterol and Mortality in Elderly Hemodialysis Patients: Data From the Korean Society of Geriatric Nephrology Retrospective Cohort.

OBJECTIVES: The association between high-density lipoprotein (HDL) cholesterol levels and mortality in elderly patients undergoing hemodialysis is not well established. Thus, this study investigated HDL levels and mortality in elderly Korean patients undergoing hemodialysis. METHODS: We recruited 1860 incident hemodialysis patients aged greater than 70 years from a retrospective cohort of the Korean Society of Geriatric Nephrology. The primary outcome measure was all-cause mortality. RESULTS: The mean age of the cohort was 77.8 years, and 1049 (56.4%) were men. When we grouped the patients into HDL cholesterol tertiles, the T1 group (HDL level <30 mg/dL in men and <33 mg/dL in women) had a higher proportion of patients with end-stage kidney disease due to diabetic nephropathy. During the median follow-up period of 3.1 years, 1109 (59.7%) deaths occurred. In a multivariable Cox regression model, the T1 group had a significantly higher risk of mortality (hazard ratio [HR], 1.28; 95% confidence interval, 1.10-1.50; P = .002) compared to the T3 group. A nonlinear analysis using a restrictive spline curve showed that low HDL cholesterol levels were associated with increased HR when HDL cholesterol levels were <40 mg/dL; however, there was no association between HDL cholesterol and mortality when HDL cholesterol levels were >40 mg/dL. Triglyceride/HDL ratio was not significantly associated with the risk of mortality (HR per 1 log increase, 1.08; 95% confidence interval, 0.99-1.18; P = .069). CONCLUSIONS: Low HDL cholesterol levels are associated with an increased risk of mortality in elderly patients undergoing hemodialysis. However, there was no significant relationship between HDL cholesterol levels and mortality when levels were below 40 mg/dL. Therefore, low HDL cholesterol levels may be a useful risk factor for predicting mortality in elderly patients undergoing hemodialysis.

Healthcare chaplains' perspectives on working with culturally diverse patients and families.

OBJECTIVES: Considering the ethnic, racial, and cultural diversity in the U.S., we aim to explore the experiences of healthcare chaplains as they provide culturally sensitive care to diverse patients and their families. METHODS: This is a qualitative study. Individual interviews were conducted with 14 healthcare chaplains recruited from 3 U.S. chaplaincy organizations. RESULTS: Thematic analysis with constant comparison yielded 6 themes in the chaplains' experiences: (1) the diverse roles of chaplains; (2) their high levels of comfort in working with diverse populations, attributed to cultural sensitivity and humility training; (3) cues for trust-building; (4) common topics of diversity, equity, and inclusion discussed; (5) gaps in chaplaincy training; and (6) the importance of collaboration and negotiation with healthcare professionals to accommodate cultural needs. SIGNIFICANCE OF RESULTS: This research highlights the valuable role of chaplains in providing culturally sensitive care and suggests areas for improving chaplaincy training and education to better serve diverse patient populations.

Service Provider Perspectives on Advance Care Planning Use in Rural Dementia Patients and Caregivers: A Qualitative Study.

Advanced care planning (ACP) utilization remains very limited in rural communities compared to urban areas. ACP earlier in the disease trajectory is particularly important for people with dementia (PWD) due to its progressive nature affecting their decision-making ability. Considering the well-documented benefits of ACP in improving the quality of end-of-life (EOL) care, the rural vs. urban disparity may indicate poorer EOL quality for rural PWD. This study aimed to explore barriers and current resources for ACP of PWD from the perspectives of health or social service providers serving rural communities. Using a qualitative approach, semi-structured face-to-face interviews were conducted with 11 health or social service professionals serving older adults and their caregivers in rural Alabama. Thematic analysis revealed three major barriers: (1) lack of knowledge, (2) psychosocial barriers, and (3) limited access to healthcare. Participants also showed misconception that a lawyer or a notary is required for ACP. Two themes arose in the participants' recommendations to address the barriers: (1) providing ACP-relevant information and (2) addressing psychosocial stressors about ACP. This study highlighted an urgent need for social policy in ACP education for caregivers and service providers in rural settings.

Changes in abdominal fat depots after bariatric surgery are associated with improved metabolic profile.

BACKGROUND AND AIMS: Obesity associated with a change in the quantity and quality of fat depots. Using computed tomography (CT), we analyzed abdominal fat depots in patients with obesity after bariatric surgery according to their metabolic health status. METHODS AND RESULTS: We recruited 79 individuals with metabolically unhealthy obesity before bariatric surgery and compared them with age-sex matched healthy controls. The volume and fat attenuation index (FAI) of fat depots were measured using CT scans that were conducted prior to and a year after bariatric surgery. 'Metabolically healthy' was defined as having no hypertension, normal fasting glucose and a waist-to-hip ratio of <1.05 for men and <0.95 for women. Individuals who achieved a metabolic health status conversion (MHC) (n = 29, 37%)-from unhealthy to healthy-were younger (p < 0.001) as compared to individuals without MHC. Pre-surgery BMI and reduction of BMI did not differ between the two groups (p = 0.099, p = 0.5730). Bariatric surgery reduced the volume and increased the FAI of fat depots. Baseline lower abdominal periaortic adipose tissue (AT) volume (p = 0.014) and great percent reduction in renal sinus AT volume after surgery (p = 0.019) were associated with MHC after surgery. Increased intraperitoneal AT FAI (p = 0.031) was also associated with MHC. CONCLUSION: MHC was not associated with improvement in general obesity, based on indicators such as reduction of BMI after surgery. Weight reduction induced specific abdominal fat depot changes measured by CT are positively associated with MHC.

Racial and ethnic differences in retrospective end-of-Life outcomes: A systematic review.

The purpose of this systematic review was to provide a comprehensive account of racial and ethnic differences in retrospective end-of-life outcomes. Studies were searched from the following databases: Abstracts in Social Gerontology, Academic Search Premier, CINAHL Plus with Full Text, ERIC, MEDLINE, PsycINFO, PubMED, and SocIndex. Studies were included if they were published in English, included people from groups who have been minoritized, included adults aged 18 and older, used retrospective data, and examined end-of-life outcomes. Results from most of the 29 included studies showed that people from groups who have been minoritized had more aggressive/intensive care, had less hospice care, were more likely to die in a hospital, less likely to engage in advance care planning, less likely to have good quality of care, and experienced more financial burden at the end of life. Implications for practice (timely referrals), policy (health insurance access), and research (intervention studies) are provided.

Resilience as a Protective Factor in Older Adult Suicide: A Rapid Review.

Nearly 700,000 suicide deaths occur each year. One in every five suicide death occurs among adults over 60 years of age or older. As the aging population increases rapidly, there is a need to understand protective factors to prevent older adult suicide. This study used the rapid review methodology to search literature from 1997 to 2022, examining whether resilience was a protective factor. The literature search was conducted over the following six databases for peer-reviewed journals and gray literature including Abstracts in Social Gerontology, Academic Search Premier, APA PsycInfo, CINAHL Complete, MEDLINE, and SocINDEX with Full Text. A total of six peer-reviewed journal articles met the inclusion criteria. The conclusion of the articles suggested resilience may be a protective factor in older adult suicide. Despite its underpinning, resilience in suicide prevention literature is lacking. More studies should examine resilience and its constructs as part of the effort to prevent older adult suicide.

Circulating miRNAs in extracellular vesicles related to treatment response in patients with idiopathic membranous nephropathy.

BACKGROUND: Extracellular vesicle (EV)-microRNAs (miRNAs) are potential biomarkers for various renal diseases. This study attempted to identify the circulating EV-miRNA signature not only for discriminating idiopathic membranous nephropathy (IMN) from idiopathic nephrotic syndrome (INS), but also to predict the treatment response of patients with IMN. METHODS: We prospectively enrolled 60 participants, including those with IMN (n = 19) and INS (n = 21) and healthy volunteers (HVs; n = 20) in this study. Using RNA sequencing, we assessed the serum EV-miRNA profiles of all participants. To identify the EV-miRNAs predictive of treatment response in IMN, we also analyzed EV-miRNAs among patients with IMN with and without clinical remission. RESULTS: The expression levels of 3 miRNAs differed between IMN patients, INS patients and HVs. In addition, compared to HVs, RNA sequencing revealed differential expression of 77 and 44 EV-miRNAs in patients with IMN without and with remission, respectively. We also identified statistically significant (|fold change ≥ 2, p < 0.05) differences in the expression levels of 23 miRNAs in IMN without remission. Biological pathway analysis of miRNAs in IMN without remission indicated that they are likely involved in various pathways, including renal fibrosis. CONCLUSION: Our study identified EV-miRNAs associated with IMN as well as those associations with therapeutic response. Therefore, these circulating EV-miRNAs may be used as potential markers for the diagnosis and prediction of treatment response in patients with IMN.

Abdominal periaortic and renal sinus fat attenuation indices measured on computed tomography are associated with metabolic syndrome.

OBJECTIVES: To investigate the association between abdominal periaortic (APA) and renal sinus (RS) fat attenuation index (FAI) measured on MDCT and metabolic syndrome in non-obese and obese individuals. METHODS: Visceral, subcutaneous, RS, and APA adipose tissue were measured in preoperative abdominal CT scans of individuals who underwent donor nephrectomy (n = 84) or bariatric surgery (n = 155). FAI was defined as the mean attenuation of measured fat volume. Participants were categorized into four groups: non-obese without metabolic syndrome (n = 64), non-obese with metabolic syndrome (n = 25), obese without metabolic syndrome (n = 21), and obese with metabolic syndrome (n = 129). The volume and FAI of each fat segment were compared among the groups. Receiver operator characteristics curve analysis was used to assess the association between the FAIs and metabolic syndrome. RESULTS: FAIs of all abdominal fat segments were significantly lower in the obese group than in the non-obese group (p < 0.001). RS, APA, and the visceral adipose tissue FAIs were significantly lower in participants with metabolic syndrome than in those without metabolic syndrome in the non-obese group (p < 0.001, p = 0.006, and p < 0.001, respectively). The area under the curve for predicting metabolic syndrome was significantly higher for APA FAI (0.790) than subcutaneous, visceral, and RS FAI in all groups (0.649, 0.647, and 0.655, respectively). CONCLUSION: Both metabolic syndrome and obesity were associated with lower RS and APA adipose tissue FAI, and APA FAI performed best for predicting metabolic syndrome. KEY POINTS: • The volume and FAI of RS, APA, and visceral adipose tissue showed opposite trends with regard to metabolic syndrome or obesity. • Both metabolic syndrome and obesity were associated with lower RS FAI and APA FAI. • APA FAI performed best for predicting metabolic syndrome among FAIs of abdominal fat segments.

Validation of an international prediction model including the Oxford classification in Korean patients with IgA nephropathy.

BACKGROUND: Recently, a new international risk prediction model including the Oxford classification was published which was validated in a large multi-ethnic cohort. Therefore, we aimed to validate this risk prediction model in Korean patients with IgA nephropathy. METHODS: This retrospective cohort study was conducted with 545 patients who diagnosed IgA nephropathy with renal biopsy in three medical centers. The primary outcome was defined as a reduction in estimated glomerular filtration rate (eGFR) of >50% or incident end-stage renal disease (ESRD). Continuous net reclassification improvement (cNRI) and integrated discrimination improvement (IDI) were used to validate models. RESULTS: During the median 3.6 years of follow-up period, 53 (9.7%) renal events occurred. In multivariable Cox regression model, M1 (hazard ratio [HR], 2.22; 95% confidence interval [CI], 1.02-4.82; p = .043), T1 (HR, 2.98; 95% CI, 1.39-6.39; p = .005) and T2 (HR, 4.80; 95% CI, 2.06-11.18; p < .001) lesions were associated with increased risk of renal outcome. When applied the international prediction model, the area under curve (AUC) for 5-year risk of renal outcome was 0.69, which was lower than previous validation and internally derived models. Moreover, cNRI and IDI analyses showed that discrimination and reclassification performance of the international model was inferior to the internally derived models. CONCLUSION: The international risk prediction model for IgA nephropathy showed not as good performance in Korean patients as previous validation in other ethnic group. Further validation of risk prediction model is needed for Korean patients with IgA nephropathy.

Educational intervention to improve palliative care knowledge among informal caregivers of cognitively impaired older adults.

OBJECTIVE: Lack of palliative care knowledge among caregivers may pose an access barrier for cognitively impaired older adults, who may benefit from the specialized care. Therefore, this study aims to examine the effectiveness of an educational intervention in improving palliative care knowledge among informal caregivers of cognitively impaired older adults. METHOD: Using a one-group, pre- and post-test intervention design, this study implemented an individual, face-to-face educational intervention with an informational brochure for 43 informal caregivers of chronically or seriously ill older adults (50+) with cognitive impairment, recruited from communities in West Alabama. Their level of knowledge about palliative care was assessed by the Palliative Care Knowledge Scale (PaCKS). The pre- and post-test scores were compared by the Wilcoxon signed-ranks test, and the racial subgroup (Whites vs. Blacks) comparison was made by the Mann-Whitney U test. RESULTS: There was a statistically significant difference between the pre- and post-test scores (z = 5.38, p < 0.001), indicating a statistically significant effect of the educational intervention in improving palliative care knowledge among participants. There was a significant difference (U = 143, p < 0.05) between Whites and Blacks in the pre-test, which, however, disappeared in the post-test (U = 173.50, p > 0.05), suggesting that the amount of increased PaCKS scores were significantly greater for Blacks (Mdn = 9.50) than for Whites (Mdn = 4.00, U = 130.50, p < 0.05). SIGNIFICANCE OF RESULTS: This study demonstrated that a one-time educational intervention can improve the level of palliative care knowledge among informal caregivers of chronically or seriously ill older adults with cognitive impairment, particularly among Black caregivers. Therefore, further educational efforts can be made to promote palliative care knowledge and reduce racial disparities in palliative care knowledge and its use.

TRIM24-RIP3 axis perturbation accelerates osteoarthritis pathogenesis.

OBJECTIVES: Recently, necroptosis has attracted increasing attention in arthritis research; however, it remains unclear whether its regulation is involved in osteoarthritis (OA) pathogenesis. Since receptor-interacting protein kinase-3 (RIP3) plays a pivotal role in necroptosis and its dysregulation is involved in various pathological processes, we investigated the role of the RIP3 axis in OA pathogenesis. METHODS: Experimental OA was induced in wild-type or Rip3 knockout mice by surgery to destabilise the medial meniscus (DMM) or the intra-articular injection of adenovirus carrying a target gene (Ad-Rip3 and Ad-Trim24 shRNA). RIP3 expression was examined in OA cartilage from human patients; Trim24, a negative regulator of RIP3, was identified by microarray and in silico analysis. Connectivity map (CMap) and in silico binding approaches were used to identify RIP3 inhibitors and to examine their direct regulation of RIP3 activation in OA pathogenesis. RESULTS: RIP3 expression was markedly higher in damaged cartilage from patients with OA than in undamaged cartilage. In the mouse model, adenoviral RIP3 overexpression accelerated cartilage disruption, whereas Rip3 depletion reduced DMM-induced OA pathogenesis. Additionally, TRIM24 knockdown upregulated RIP3 expression; its downregulation promoted OA pathogenesis in knee joint tissues. The CMap approach and in silico binding assay identified AZ-628 as a potent RIP3 inhibitor and demonstrated that it abolished RIP3-mediated OA pathogenesis by inhibiting RIP3 kinase activity. CONCLUSIONS: TRIM24-RIP3 axis perturbation promotes OA chronicity by activating RIP3 kinase, suggesting that the therapeutic manipulation of this pathway could provide new avenues for treating OA.

Melatonin-stimulated exosomes enhance the regenerative potential of chronic kidney disease-derived mesenchymal stem/stromal cells via cellular prion proteins.

Chronic kidney disease (CKD) is caused by dysfunctional kidneys, which result in complications like cardiovascular diseases. Chronic kidney disease-induced pathophysiological conditions decrease efficacy of autologous mesenchymal stem/stromal cell (MSC)-based therapy by reducing MSC functionality. To enhance therapeutic potential in patients with CKD, we isolated exosomes derived from melatonin-treated healthy MSCs (MT exosomes) and assessed the biological functions of MT exosome-treated MSCs isolated from patients with CKD (CKD-MSCs). Treatment with melatonin increased the expression of cellular prion protein (PrPC ) in exosomes isolated from MSCs through the upregulation of miR-4516. Treatment with MT exosomes protected mitochondrial function, cellular senescence, and proliferative potential of CKD-MSCs. MT exosomes significantly increased the level of angiogenesis-associated proteins in CKD-MSCs. In a murine hindlimb ischemia model with CKD, MT exosome-treated CKD-MSCs improved functional recovery and vessel repair. These findings elucidate the regenerative potential of MT exosome-treated CKD-MSCs via the miR-4516-PrPC signaling axis. This study suggests that the treatment of CKD-MSCs with MT exosomes might be a powerful strategy for developing autologous MSC-based therapeutics for patients with CKD. Furthermore, miR-4516 and PrPC could be key molecules for enhancing the regenerative potential of MSCs in ischemic diseases.

The circulating exosomal microRNAs related to albuminuria in patients with diabetic nephropathy.

BACKGROUND: Diabetic nephropathy (DN) is associated with high risk of cardiovascular disease and mortality. Exosomal microRNAs (miRNAs) regulate gene expression in a variety of tissues and play important roles in the pathology of various diseases. We hypothesized that the exosomal miRNA profile would differ between DN patients and patients without nephropathy. METHODS: We prospectively enrolled 74 participants, including healthy volunteers (HVs), diabetic patients without nephropathy, and those with DN. The serum exosomal miRNA profiles of participants were examined using RNA sequencing. RESULTS: The expression levels of 107 miRNAs differed between HVs and patients without DN, whereas the expression levels of 95 miRNAs differed between HVs and patients with DN. Among these miRNAs, we found 7 miRNAs (miR-1246, miR-642a-3p, let-7c-5p, miR-1255b-5p, let-7i-3p, miR-5010-5p, miR-150-3p) that were uniquely up-regulated in DN patients compared to HVs, and miR-4449 that was highly expressed in DN patients compared to patients without DN. A pathway analysis revealed that these eight miRNAs are likely involved in MAPK signaling, integrin function in angiogenesis, and regulation of the AP-1 transcription factor. Moreover, they were all significantly correlated with the degree of albuminuria. CONCLUSIONS: Patients with DN have a different serum exosomal miRNA profile compared to HVs. These miRNAs may be promising candidates for the diagnosis and treatment of DN and cardiovascular disease.

Melatonin protects chronic kidney disease mesenchymal stem cells against senescence via PrPC -dependent enhancement of the mitochondrial function.

Although mesenchymal stem cell (MSC)-based therapy is a treatment strategy for ischemic diseases associated with chronic kidney disease (CKD), MSCs of CKD patients undergo accelerated senescence, with decreased viability and proliferation upon uremic toxin exposure, inhibiting their utility as a potent stem cell source for transplantation therapy. We investigated the effects of melatonin administration in protecting against cell senescence and decreased viability induced by pathophysiological conditions near the engraftment site. MSCs harvested from CKD mouse models were treated with H2 O2 to induce oxidative stress. CKD-derived MSCs exhibited greater oxidative stress-induced senescence than normal-mMSCs, while melatonin protected CKD-mMSCs from H2 O2 and associated excessive senescence. The latter was mediated by PrPC -dependent mitochondrial functional enhancement; melatonin upregulated PrPC , which bound PINK1, thus promoting mitochondrial dynamics and metabolism. In vivo, melatonin-treated CKD-mMSCs survived longer, with increased secretion of angiogenic cytokines in ischemic disease engraftment sites. CKD-mMSCs are more susceptible to H2 O2 -induced senescence than normal-mMSCs, and melatonin administration protects CKD-mMSCs from excessive senescence by upregulating PrPC and enhancing mitochondrial function. Melatonin showed favorable therapeutic effects by successfully protecting CKD-mMSCs from related ischemic conditions, thereby enhancing angiogenesis and survival. These results elucidate the mechanism underlying senescence inhibition by melatonin in stem cell-based therapies using mouse-derived CKD-mMSCs.

A comparison of urban and non-urban African American older adults on health-related characteristics.

Although residential geographic health disparities have been noted in the previous literature, studies are specifically lacking on intra-group health comparisons of African American older adults by residential geography. The purpose of this study was to determine if health-related characteristics of African American older adults varied by residential geography. Socioeconomic demographics, medical conditions, primary care use, and self-ratings of general health, social activity, and physical activity were compared in a community-dwelling sample of 327 urban and non-urban African American older adults. Urban and non-urban African American older adults were compared on health-related factors. Compared to urban African American older adults, those in non-urban areas had lower incomes, lower self-ratings of general health, social activity, and physical activity, and a higher frequency of arthritis and gastroenterological and urological conditions. Despite poorer general health and medical conditions, non-urban African American older adults were less likely to visit the doctor when needed. Study findings suggest residential geography may be an underappreciated underlying contributing factor to inter-group health disparities between African American and white older adults and not race alone. Therefore, social workers in public health, health care, and clinical settings should be aware of the interaction between race and residential geography.

Beta 2-adrenergic receptor agonists are novel regulators of macrophage activation in diabetic renal and cardiovascular complications.

Macrophage activation is increased in diabetes and correlated with the onset and progression of vascular complications. To identify drugs that could inhibit macrophage activation, we developed a cell-based assay and screened a 1,040 compound library for anti-inflammatory effects. Beta2-adrenergic receptor (ß2AR) agonists were identified as the most potent inhibitors of phorbol myristate acetate-induced tumor necrosis factor-α production in rat bone marrow macrophages. In peripheral blood mononuclear cells isolated from streptozotocin-induced diabetic rats, ß2AR agonists inhibited diabetes-induced tumor necrosis factor-α production, which was prevented by co-treatment with a selective ß2AR blocker. To clarify the underlying mechanisms, THP-1 cells and bone marrow macrophages were exposed to high glucose. High glucose reduced ß-arrestin2, a negative regulator of NF-κB activation, and its interaction with IκBα. This subsequently enhanced phosphorylation of IκBα and activation of NF-κB. The ß2AR agonists enhanced ß-arrestin2 and its interaction with IκBα, leading to downregulation of NF-κB. A siRNA specific for ß-arrestin2 reversed ß2AR agonist-mediated inhibition of NF-κB activation and inflammatory cytokine production. Treatment of Zucker diabetic fatty rats with a ß2AR agonist for 12 weeks attenuated monocyte activation as well as pro-inflammatory and pro-fibrotic responses in the kidneys and heart. Thus, ß2AR agonists might have protective effects against diabetic renal and cardiovascular complications.

Fucoidan improves bioactivity and vasculogenic potential of mesenchymal stem cells in murine hind limb ischemia associated with chronic kidney disease.

Chronic kidney disease (CKD) is a significant risk factor for cardiovascular and peripheral vascular disease. Although mesenchymal stem cell (MSC)-based therapy is a promising strategy for treatment of ischemic diseases associated with CKD, the associated pathophysiological conditions lead to low survival and proliferation of transplanted MSCs. To address these limitations, we investigated the effects of fucoidan, a sulfated polysaccharide, on the bioactivity of adipose tissue-derived MSCs and the potential of fucoidan-treated MSCs to improve neovascularization in ischemic tissues of CKD mice. Treatment of MSCs with fucoidan increased their proliferative potential and the expression of cell cycle-associated proteins, such as cyclin E, cyclin dependent kinase (CDK) 2, cyclin D1, and CDK4, via focal adhesion kinase and the phosphatidylinositol-4,5-bisphosphate 3-kinase-Akt axis. Moreover, fucoidan enhanced the immunomodulatory activity of MSCs through the ERK-IDO-1 signal cascade. Fucoidan was found to augment the proliferation, incorporation, and endothelial differentiation of transplanted MSCs at ischemic sites in CKD mice hind limbs. In addition, transplantation of fucoidan-treated MSCs enhanced the ratio of blood flow and limb salvage in CKD mice with hind limb ischemia. To our knowledge, our findings are the first to reveal that fucoidan enhances the bioactivity of MSCs and improves their neovascularization in ischemic injured tissues of CKD. In conclusion, fucoidan-treated MSCs may provide an important pathway toward therapeutic neovascularization in patients with CKD.