APOL1 CKD Risk Alleles in New Mexico African American and American Indian Populations: Racial Disparity

Purpose/Background: Two haplotypes of human apolipoprotein L1 gene (gene: APOL1; protein: ApoL1) harboring three coding sequence mutations have been demonstrated as risk variants associated with non-diabetic chronic kidney diseases (CKD) in African Americans. The first one, termed G1, is a two non-synonymous SNP haplotype (rs73885319 (A\u3eG; p.S342G) and rs60910145 (G\u3eT; p.I384M). The second one, termed G2, is a two codon deletion haplotype rs71785313 (6-bp in frame deletion) These two coding-sequence variants have been discovered in CKD patients of African ancestry and linked to the pathogenesis of primary focal and segmental glomerulosclerosis (FSGS), hypertension-attributed kidney disease, and HIV-associated nephropathy (HIVAN), under a recessive inheritance pattern. Marked disparities exist in races, rates, and etiological classifications of CDK between African Americans (AAs) and European Americans. Sequencing and genotyping analysis of known APOL1 SNPs showed that only APOL1 G1 and G2 confer kidney risk, and other common and rare APOL1 missense variants, including the G3 haplotype, do not contribute to FSGS and HIVAN in the US population. According to the report of US census bureau, African American and American Indian (AI) citizens in New Mexico make up nearly 2.5% and 10.9% of the state\u27s entire population in 2018 (2). However, whether APOL1 G1 and G2 kidney-risk alleles are linked with hypertension-attributed CKD in AAs and AIs in New Mexico has not been investigated. Materials & Methods: We analyzed the published results of a retrospective analysis of inpatient and discharge data from hospitals across the state of New Mexico, known as Hospital Inpatient and Discharge Dataset (HIDD; 3). Results: A pattern persisted for all three years (2012-2014) that AAs had the highest rate of CKD followed by AIs per 10,000 population in New Mexico. AAs had the highest age adjusted rate of CKD with hypertension at 102.6 per 10,000 population (29.7% (102.6/345.7) of all CKD with hypertension patients) followed by American Indians at 91.9 (26.6% (91.9/345.7) of all CKD with hypertension patients). Interestingly, in terms of CKD with diabetes, AIs had the highest age adjusted rate at 79.9 per 10,000 followed by AAs at 66.5. Discussion/Conclusion: The prevalence of CKD with hypertension in AA and AI populations is significantly high in New Mexico, To understand the etiology of CKD in AAs and AIs in New Mexico, genotyping the APOL1 G1 and G2 risk alleles in these two populations is warranted. Detection of APOL1 associations with CKD and delineation of injury pathways (autophagy, necroptosis and ferroptosis) would bring hope for effective treatment for these kidney diseases. In addition, modifier loci can influence APOL1 risk for the development of CKD. ‘Second hits’, for example viral and environmental, may alter the outcome of APOL1 risk variants

How Complicated Can It Be? The Link Between APOL1 Risk Variants and Lipoprotein Heterogeneity in Kidney and Cardiovascular Diseases.

The beginning of human apolipoprotein L1 study (gene: APOL1; protein: ApoL1) originated from the identification of circulating ApoL1 as an interacting protein of ApoA1 and a minor component of high-density lipoprotein subfraction 3 (HDL3) in 1997 [1]. In the past 18 years, ApoL1 has been investigated in the context of complex human diseases such as African sleeping sickness, schizophrenia, host innate immunity, cancer, hyperlipidemia, cardiovascular diseases, stroke and type 2 diabetes [2–10]. A major breakthrough, however, was the documentation of two haplotypes of APOL1, harboring three coding-sequence mutations as risk variants associated with non-diabetic chronic kidney diseases (CKD) in African Americans [5, 6]. The first one, termed G1, is a two non-synonymous SNP haplotype [rs73885319 (A \u3e G; p.S342G) and rs60910145 (G \u3e T; p.I384M)]. The second one, termed G2, is a two codon deletion haplotype rs71785313 (6-bp in frame deletion; p.ΔN388Y389) [4, 5]. These two coding-sequence variants have been discovered mainly in kidney disease patients of African ancestry and linked to the pathogenesis of primary focal and segmental glomerulosclerosis, hypertension-attributed kidney disease and HIV-associated nephropathy (HIVAN), under a recessive inheritance pattern [3, 7, 10]. Moreover, these APOL1 variants and African American recipient ethnicity have been shown to associate with kidney transplant rejection and allograft failure [11–13]. Importantly, the expression of ApoL1 has been detected in renal proximal tubular epithelial cells, podocytes, medium-sized arteries, arteriolar endothelial cells and pre-glomerular vascular structures [3, 14, 15]. Thus, there is no doubt or controversy regarding the notion that the expression of APOL1 risk alleles in kidney cells is associated with the development and progression of non-diabetic CKD in African Americans. In fact, we and others have shown that interferon-α, -β and -γ and TNF-α can induce the expression of ApoL1 in endothelial cells and overexpression of ApoL1 can lead to autophagy- and/or necrosis-associated cell death in a variety of cell types, including endothelial cells and podocytes [15–19]. However, the role of ApoL1 in the outcome of cardiovascular diseases is a much more controversial topic [20]. Some studies suggest that the APOL1 risk alleles have an adverse effect [8], while others failed to detect an association between the risk alleles and these cardiovascular events [9], or showed improved survival in patients with two risk alleles [10]. Moreover, the potential role that extracellular/circulating ApoL1 might have on systemic endothelial and/or kidney cells is currently unknown. It is worth noting that besides being a component of HDL, ApoL1 is also a component of very low density lipoproteins (VLDL) and LDL [21]. This fact, however, has been frequently overlooked and the role of ApoL1 in VLDL and LDL has not been explored. In this issue, Gutierrez et al. [22] utilized a case–control sample of African Americas who were part of the Sea Islands Genetics Network (SIGNET) and assessed the relationship between the APOL1 risk variants, G1 and G2, and the circulating levels of different lipoproteins and sizes of HDL subclasses measured by nuclear magnetic resonance (NMR) spectroscopy. Using this well-established NMR technique, which is based on the assessment of distinct methyl groups of lipid species in plasma samples [23, 24], they found a modest increase of small-size HDL particles (small HDL) in the circulation of patients carrying the APOL1 G1/G2 risk alleles, independently of age, sex, diabetes and percentage of African ancestry. There were no significant differences in large or medium HDL, VLDL or LDL concentrations observed by APOL1 genotype in this study. Although the classification of large, medium and small of HDL is different from that of HDL 1, 2 and 3 subfractions defined by the density/density centrifugation [25–28], the small HDL should be lipid-poor and high density similar to, if not the same as, HDL3, of which ApoL1 is a component [1]. However, in this study the levels of ApoL1 in plasma samples were not measured and therefore cannot be correlated to the levels of small HDL or other lipoprotein particles. The results of Gutierrez et al. may be clinically relevant, since they suggest that the APOL1 genotype could play a direct role in determining the circulating concentration of small HDL, which have been associated with renal and cardiovascular diseases [7–10, 27]. However, as discussed in their article, these findings should be interpreted with caution. The authors propose that the APOL1 risk variants could contribute to the increase prevalence of renal disease by facilitating the formation of circulating HDL subpopulations with pro-atherogenic properties. Nonetheless, the difference in the circulating levels of small HDL between subjects with zero and two APOL1 risk alleles was modest (0.9 µmol/L), and although a previous study found that changes of this magnitude could be associated with albuminuria [27], no differences were found in the prevalence of CKD, albuminuria or other markers of cardiometabolic status across all the APOL1 categories in the subjects of this study [22]. In addition, the difference in small HDL concentration between individuals with one risk allele versus two risk alleles was minor (0.2 μmol/L) and very unlikely to be clinically relevant. Moreover, if two APOL1 risk alleles and higher circulating concentrations of small HDL interact to precipitate CKD, one should ask why two APOL1 risk alleles do not increase risk of diabetic nephropathy in African Americans with elevated HDL3. If the role of APOL1 rick alleles is to increase the concentration of small HDL (or HDL3), then adding elevated HDL3 is redundant; if the small HDL (or HDL3) are elevated already due to other factors, then APOL1 rick alleles cannot play an additional role by increasing small HDL (or HDL3). On the other hand, it is well known that once diabetic nephropathy is established, the progression of the renal disease is accelerated in patients carrying two APOL1 risk alleles [7]. In summary, given the negligible difference reported between the circulating levels of small HDL in patients carrying one versus two risk alleles (0.2 μmol/L), these changes are very unlikely to explain the increase risk of CKD conferred only by two risk alleles. As an alternative explanation, Gutierrez et al. argue that the elevated levels of small HDL could be due to changes in renal metabolic pathways. In this regard, a previous study showed that cubilin (gene: CUBN; protein: cubilin), an endocytic receptor highly expressed in renal proximal tubules, mediates the uptake of albumin and filtered forms of ApoA1-HDL [29]. Moreover, CUBN heterozygous deficient mice and transgenic mice overexpressing human cubilin showed either decreased or elevated levels of ApoA1, HDL cholesterol and HDL3 particles, respectively [29]. Nonetheless, the subjects carrying two risk alleles of APOL1 in the Gutierrez study showed only a minor increase in the circulating concentration of small HDL, suggesting that this isolated change is unlikely to be the result of renal metabolism. Taken together, the findings of Gutierrez et al. [22] add more fuel to the ongoing controversy regarding the association of APOL1 G1/G2 risk status with cardiovascular outcome among African Americans. However, if one speculates that the APOL1 risk alleles may directly modify the circulating levels of small HDL and/or other factors and induce a pro-atherogenic state that precipitates CKD and cardiovascular complications, then one should begin to answer the following several questions. (i) Why are the APOL1 risk variants not associated with an increased prevalence of diabetic nephropathy in African Americans? (ii) Would the APOL1 risk alleles alter the synthesis and function of other proteins in HDL3, VLDL and VDL? (iii) How do the circulating ApoL1 mutant proteins interact with the plasma membrane and initiate a signal transduction pathway from outside to inside of the targeted cell? (iv) What mechanisms modulate the transport of circulating ApoL1 mutant proteins inside the cells and its interaction with intracellular ApoL1 and/or other intracellular proteins, for example, apolipoprotein L6 (ApoL6), an ApoL1-related protein, which when overexpressed, induces atherosclerotic apoptosis [30]? Finally, as the expression of ApoL1 can be induced by inflammatory cytokines and intracellular accumulation of ApoL1 can initiate autophagy and cell death in endothelia cells, the crosstalk between inflammation, autophagy and cell death mediated by the overexpression of ApoL1 should be much more intensively investigated before one can properly interpret the meaning of these findings reported by Gutierrez et al. [22]

Deacetylation of p53 induces autophagy by suppressing Bmf expression

Interferon γ (IFN-γ)–induced cell death is mediated by the BH3-only domain protein, Bik, in a p53-independent manner. However, the effect of IFN-γ on p53 and how this affects autophagy have not been reported. The present study demonstrates that IFN-γ down-regulated expression of the BH3 domain-only protein, Bmf, in human and mouse airway epithelial cells in a p53-dependent manner. p53 also suppressed Bmf expression in response to other cell death–stimulating agents, including ultraviolet radiation and histone deacetylase inhibitors. IFN-γ did not affect Bmf messenger RNA half-life but increased nuclear p53 levels and the interaction of p53 with the Bmf promoter. IFN-γ–induced interaction of HDAC1 and p53 resulted in the deacetylation of p53 and suppression of Bmf expression independent of p53’s proline-rich domain. Suppression of Bmf facilitated IFN-γ–induced autophagy by reducing the interaction of Beclin-1 and Bcl-2. Furthermore, autophagy was prominent in cultured bmf−/− but not in bmf+/+ cells. Collectively, these observations show that deacetylation of p53 suppresses Bmf expression and facilitates autophagy

Image-guided intensity modulated radiotherapy with helical tomotherapy for postoperative treatment of high-risk oral cavity cancer

<p>Abstract</p> <p>Background</p> <p>The aim of this study was to assess the treatment results and toxicity profiles of helical tomotherapy (HT) for postoperative high-risk oral cavity cancer.</p> <p>Methods</p> <p>From December 6, 2006 through October 9, 2009, 19 postoperative high-risk oral cavity cancer patients were enrolled. All of the patients received HT with (84%) or without (16%) chemotherapy.</p> <p>Results</p> <p>The median follow-up time was 17 months. The 2-year overall survival, disease-free survival, locoregional control, and distant metastasis-free rates were 94%, 84%, 92%, and 94%, respectively. The package of overall treatment time > 13 wk, the interval between surgery and radiation ≤ 6 wk, and the overall treatment time of radiation ≤ 7 wk was 21%, 84%, and 79%, respectively. The percentage of grade 3 mucositis, dermatitis, and leucopenia was 42%, 5% and 5%, respectively.</p> <p>Conclusions</p> <p>HT achieved encouraging clinical outcomes for postoperative high-risk oral cavity cancer patients with high compliance. A long-term follow-up study is needed to confirm these preliminary findings.</p

Variants in autophagy-related genes and clinical characteristics in melanoma: a population-based study

Autophagy has been linked with melanoma risk and survival, but no polymorphisms in autophagy-related (ATG) genes have been investigated in relation to melanoma progression. We examined five single-nucleotide polymorphisms (SNPs) in three ATG genes (ATG5; ATG10; and ATG16L) with known or suspected impact on autophagic flux in an international population-based case-control study of melanoma. DNA from 911 melanoma patients was genotyped. An association was identified between (GG) (rs2241880) and earlier stage at diagnosis (OR 0.47; 95% Confidence Intervals (CI) = 0.27-0.81, P = 0.02) and a decrease in Breslow thickness (P = 0.03). The ATG16L heterozygous genotype (AG) (rs2241880) was associated with younger age at diagnosis (P = 0.02). Two SNPs in ATG5 were found to be associated with increased stage (rs2245214 CG, OR 1.47; 95% CI = 1.11-1.94, P = 0.03; rs510432 CC, OR 1.84; 95% CI = 1.12-3.02, P = 0.05). Finally, we identified inverse associations between ATG5 (GG rs2245214) and melanomas on the scalp or neck (OR 0.20, 95% CI = 0.05-0.86, P = 0.03); ATG10 (CC) (rs1864182) and brisk tumor infiltrating lymphocytes (TILs) (OR 0.42; 95% CI = 0.21-0.88, P = 0.02), and ATG5 (CC) (rs510432) with nonbrisk TILs (OR 0.55; 95% CI = 0.34-0.87, P = 0.01). Our data suggest that ATG SNPs might be differentially associated with specific host and tumor characteristics including age at diagnosis, TILs, and stage. These associations may be critical to understanding the role of autophagy in cancer, and further investigation will help characterize the contribution of these variants to melanoma progression

Akt-Induced Phosphorylation of N-CoR at Serine 1450 Contributes to Its Misfolded Conformational Dependent Loss (MCDL) in Acute Myeloid Leukemia of the M5 Subtype

10.1371/journal.pone.0070891PLoS ONE88-POLN

Gastrodin Inhibits Allodynia and Hyperalgesia in Painful Diabetic Neuropathy Rats by Decreasing Excitability of Nociceptive Primary Sensory Neurons

Painful diabetic neuropathy (PDN) is a common complication of diabetes mellitus and adversely affects the patients’ quality of life. Evidence has accumulated that PDN is associated with hyperexcitability of peripheral nociceptive primary sensory neurons. However, the precise cellular mechanism underlying PDN remains elusive. This may result in the lacking of effective therapies for the treatment of PDN. The phenolic glucoside, gastrodin, which is a main constituent of the Chinese herbal medicine Gastrodia elata Blume, has been widely used as an anticonvulsant, sedative, and analgesic since ancient times. However, the cellular mechanisms underlying its analgesic actions are not well understood. By utilizing a combination of behavioral surveys and electrophysiological recordings, the present study investigated the role of gastrodin in an experimental rat model of STZ-induced PDN and to further explore the underlying cellular mechanisms. Intraperitoneal administration of gastrodin effectively attenuated both the mechanical allodynia and thermal hyperalgesia induced by STZ injection. Whole-cell patch clamp recordings were obtained from nociceptive, capsaicin-sensitive small diameter neurons of the intact dorsal root ganglion (DRG). Recordings from diabetic rats revealed that the abnormal hyperexcitability of neurons was greatly abolished by application of GAS. To determine which currents were involved in the antinociceptive action of gastrodin, we examined the effects of gastrodin on transient sodium currents (INaT) and potassium currents in diabetic small DRG neurons. Diabetes caused a prominent enhancement of INaT and a decrease of potassium currents, especially slowly inactivating potassium currents (IAS); these effects were completely reversed by GAS in a dose-dependent manner. Furthermore, changes in activation and inactivation kinetics of INaT and total potassium current as well as IAS currents induced by STZ were normalized by GAS. This study provides a clear cellular basis for the peripheral analgesic action of gastrodin for the treatment of chronic pain, including PDN

Fatty Acid Biomarkers of Dairy Fat Consumption and Incidence of Type 2 Diabetes: A Pooled Analysis of Prospective Cohort Studies

Background We aimed to investigate prospective associations of circulating or adipose tissue odd-chain fatty acids 15:0 and 17:0 and trans-palmitoleic acid, t16:1n-7, as potential biomarkers of dairy fat intake, with incident type 2 diabetes (T2D). Methods and findings Sixteen prospective cohorts from 12 countries (7 from the United States, 7 from Europe, 1 from Australia, 1 from Taiwan) performed new harmonised individual-level analysis for the prospective associations according to a standardised plan. In total, 63,682 participants with a broad range of baseline ages and BMIs and 15,180 incident cases of T2D over the average of 9 years of follow-up were evaluated. Study-specific results were pooled using inverse-variance±weighted meta-analysis. Prespecified interactions by age, sex, BMI, and race/ethnicity were explored in each cohort and were meta-analysed. Potential heterogeneity by cohort-specific characteristics (regions, lipid compartments used for fatty acid assays) was assessed with metaregression. After adjustment for potential confounders, including measures of adiposity (BMI, waist circumference) and lipogenesis (levels of palmitate, triglycerides), higher levels of 15:0, 17:0, and t16:1n-7 were associated with lower incidence of T2D. In the most adjusted model, the hazard ratio (95% CI) for incident T2D per cohortspecific 10th to 90th percentile range of 15:0 was 0.80 (0.73±0.87); of 17:0, 0.65 (0.59± 0.72); of t16:1n7, 0.82 (0.70±0.96); and of their sum, 0.71 (0.63±0.79). In exploratory analyses, similar associations for 15:0, 17:0, and the sum of all three fatty acids were present in both genders but stronger in women than in men (pinteraction \u3c 0.001). Whereas studying associations with biomarkers has several advantages, as limitations, the biomarkers do not distinguish between different food sources of dairy fat (e.g., cheese, yogurt, milk), and residual confounding by unmeasured or imprecisely measured confounders may exist. Conclusions In a large meta-analysis that pooled the findings from 16 prospective cohort studies, higher levels of 15:0, 17:0, and t16:1n-7 were associated with a lower risk of T2D

Fatty acids in the de novo lipogenesis pathway and incidence of type 2 diabetes: A pooled analysis of prospective cohort studies

Funder: Dutch Scientific OrganizationFunder: Foundation Plan AlzheimerFunder: Icelandic Heart AssociationFunder: Academy of FinlandFunder: VicHealth and Cancer Council VictoriaFunder: Juselius FoundationFunder: Uppsala University Hospital and the Swedish Research Council for Health, Working Life and WelfareFunder: the Institut National de la Sante et de la Recherche MedicaleFunder: , the University Bordeaux 2 Victor SegalenFunder: Sanofi; funder-id: http://dx.doi.org/10.13039/100004339Funder: Fondation pour la Recherche Medicale, the Caisse Nationale Maladie des Travailleurs Salaries, Direction Generale de la Sante, MGEN, Institut de la Longevite, Conseils Regionaux d’Aquitaine et Bourgogne, Fondation de France, Ministry of Research–Institut National de la Sante and de la Recherche Medicale Programme CohortesFunder: Caisse Nationale pour la Solidarite et l’AutonomieFunder: Swedish Research Council for Health, Working Life and Welfare, Uppsala City Council, Swedish Research Council, and Swedish Diabetes FoundationBackground: De novo lipogenesis (DNL) is the primary metabolic pathway synthesizing fatty acids from carbohydrates, protein, or alcohol. Our aim was to examine associations of in vivo levels of selected fatty acids (16:0, 16:1n7, 18:0, 18:1n9) in DNL with incidence of type 2 diabetes (T2D). Methods and findings: Seventeen cohorts from 12 countries (7 from Europe, 7 from the United States, 1 from Australia, 1 from Taiwan; baseline years = 1970–1973 to 2006–2010) conducted harmonized individual-level analyses of associations of DNL-related fatty acids with incident T2D. In total, we evaluated 65,225 participants (mean ages = 52.3–75.5 years; % women = 20.4%–62.3% in 12 cohorts recruiting both sexes) and 15,383 incident cases of T2D over the 9-year follow-up on average. Cohort-specific association of each of 16:0, 16:1n7, 18:0, and 18:1n9 with incident T2D was estimated, adjusted for demographic factors, socioeconomic characteristics, alcohol, smoking, physical activity, dyslipidemia, hypertension, menopausal status, and adiposity. Cohort-specific associations were meta-analyzed with an inverse-variance-weighted approach. Each of the 4 fatty acids positively related to incident T2D. Relative risks (RRs) per cohort-specific range between midpoints of the top and bottom quintiles of fatty acid concentrations were 1.53 (1.41–1.66; p < 0.001) for 16:0, 1.40 (1.33–1.48; p < 0.001) for 16:1n-7, 1.14 (1.05–1.22; p = 0.001) for 18:0, and 1.16 (1.07–1.25; p < 0.001) for 18:1n9. Heterogeneity was seen across cohorts (I2 = 51.1%–73.1% for each fatty acid) but not explained by lipid fractions and global geographical regions. Further adjusted for triglycerides (and 16:0 when appropriate) to evaluate associations independent of overall DNL, the associations remained significant for 16:0, 16:1n7, and 18:0 but were attenuated for 18:1n9 (RR = 1.03, 95% confidence interval (CI) = 0.94–1.13). These findings had limitations in potential reverse causation and residual confounding by imprecisely measured or unmeasured factors. Conclusions: Concentrations of fatty acids in the DNL were positively associated with T2D incidence. Our findings support further work to investigate a possible role of DNL and individual fatty acids in the development of T2D

Omega-6 Fatty Acid Biomarkers and Incident Type 2 Diabetes: Pooled Analysis of Individual-Level Data for 39 740 Adults from 20 Prospective Cohort Studies

Background: The metabolic effects of omega-6 polyunsaturated fatty acids (PUFAs) remain contentious, and little evidence is available regarding their potential role in primary prevention of type 2 diabetes. We aimed to assess the associations of linoleic acid and arachidonic acid biomarkers with incident type 2 diabetes. Methods: We did a pooled analysis of new, harmonised, individual-level analyses for the biomarkers linoleic acid and its metabolite arachidonic acid and incident type 2 diabetes. We analysed data from 20 prospective cohort studies from ten countries (Iceland, the Netherlands, the USA, Taiwan, the UK, Germany, Finland, Australia, Sweden, and France), with biomarkers sampled between 1970 and 2010. Participants included in the analyses were aged 18 years or older and had data available for linoleic acid and arachidonic acid biomarkers at baseline. We excluded participants with type 2 diabetes at baseline. The main outcome was the association between omega-6 PUFA biomarkers and incident type 2 diabetes. We assessed the relative risk of type 2 diabetes prospectively for each cohort and lipid compartment separately using a prespecified analytic plan for exposures, covariates, effect modifiers, and analysis, and the findings were then pooled using inverse-variance weighted meta-analysis. Findings: Participants were 39 740 adults, aged (range of cohort means) 49-76 years with a BMI (range of cohort means) of 23·3-28·4 kg/m(2), who did not have type 2 diabetes at baseline. During a follow-up of 366 073 person-years, we identified 4347 cases of incident type 2 diabetes. In multivariable-adjusted pooled analyses, higher proportions of linoleic acid biomarkers as percentages of total fatty acid were associated with a lower risk of type 2 diabetes overall (risk ratio [RR] per interquintile range 0·65, 95% CI 0·60-0·72,