Translation of a Diabetes Remission Service into Australian Primary Care: Findings from the Evaluation of DiRECT-Australia.

Background: The Diabetes Remission Clinical Trial (DiRECT) study demonstrated that an intensive and structured weight management program in UK primary care resulted in high rates of diabetes remission in adults with recent onset type 2 diabetes mellitus (T2DM). This study was aimed at evaluating the translation of the DiRECT intervention into an Australian primary care setting. Methods: All patients enrolled in the DiRECT-Australia Type 2 Diabetes Remission Service in a region of Sydney (Macarthur region, South Western Sydney, Australia) were included. Eligible participants were aged 20-70 years, noninsulin treated, with T2DM of ≤6 years' duration, and body mass index (BMI) ≥ 27 kg/m2. Total diet replacement of 825-853 kcal/day using meal replacements was implemented for 12 weeks, followed by an ongoing structured program until 52 weeks, with regular follow-up with a general practitioner, dietitian, and/or practice nurse. Results: Of 39 recruited participants, 32 (82.1%) and 27 (69.2%) completed 12 weeks and 52 weeks of the structured program, respectively. Decrease in weight by -12.0 kg (95% CI: -9.6, -14.4; p < 0.001) and -9.1 kg (95% CI: -5.2, -12.9; p < 0.001) and decrease in glycated haemoglobin (HbA1c) by -1.1% (95% CI: -0.6, -1.6; p < 0.001) and -0.6% (95% CI: -0.1, -1.1; p = 0.013) were observed at 12 and 52 weeks, respectively. At the end of 12 and 52 weeks, 93.8% (30/32) and 55.6% (15/27) of those with follow-up data met the criteria for diabetes remission, respectively. Quality of life and wellbeing scores increased over the course of 12 weeks, remaining significantly higher at 52 weeks. Participants reported they would be willing to pay A$92.50 (95% CI: A$75.80, A$109.30) per fortnight for the low-calorie meal replacement shakes. Conclusions: These findings support the feasibility of a structured diabetes remission service in an Australian primary care setting to achieve improvements in glycaemia, weight, and quality of life and wellbeing, and suggest a substantial willingness to pay for diet replacement products among participants.

The Effects of Yogurt Supplementation and Nutritional Education on Malnourished Infants: A Pilot RCT in Dhaka's Slums.

Our objective was to quantify the effects of yogurt supplementation and nutrition education over three months on the linear growth of infants at risk of stunting. We conducted a three-arm pilot randomized controlled trial: (1) nutrition education for mothers; (2) nutrition education plus a daily yogurt supplement (50 g) for the index child; and (3) usual care (control). Dyads of children aged 4-6 months and at risk of stunting [length-for-age z-score (LAZ) ≤ -1 SD and >-2 SD] and their mothers with ≤10 years of education were eligible for the study. Participants were recruited from five slum areas in Dhaka, Bangladesh. Intention-to-treat (N = 162) and complete-case analyses (N = 127) showed no between-group statistically significant differences in LAZ or weight-for-age (WAZ). However, the yogurt group showed greater change in linear growth compared to the control (LAZ: mean difference 0.20, 95% CI: -0.06, 0.47, p-value 0.13), which was also slightly greater than the education-only group. Children in the yogurt plus group were five times (95% CI: 0.80, 31.80, p-value 0.09) more likely to meet the minimum dietary diversity (MDD) score compared to the control. A 3-month follow-up of this pilot study did not demonstrate that yogurt was beneficial to linear growth. However, there were encouraging trends that merit replication of the intervention with larger samples and longer follow-ups.

Mental illness stigma and associated factors among Arabic-speaking refugee and migrant populations in Australia.

BACKGROUND: Arabic-speaking refugee and migrant populations form a significant proportion of Australia's population. Despite high levels of psychological distress among Arabic-speaking populations, low uptake of mental health services has been demonstrated. Evidence suggests poor levels of mental health literacy (MHL) and high levels of stigmatising attitudes among Arabic-speaking populations, which may act as barriers to help-seeking behaviours. This study aimed to explore the relationships between measures of mental illness stigma, socio-demographic factors and psychological distress, as well as to determine the factors associated with MHL (i.e., correct recognition of mental illness and knowledge of causes) among Arabic-speaking refugee and migrant populations in Australia. METHODS: Participants were recruited from non-government organisations in Greater Western Sydney that provided support services to Arabic-speaking migrants and/or refugees. As this study is nested within an interventional pilot study evaluating a culturally tailored MHL program, only the pre-intervention survey responses for 53 participants were utilised. The survey measured key aspects of MHL (i.e., recognition of mental illness, knowledge of causes), levels of psychological distress (using K10 scale), and stigmatising attitudes towards mental illness (using Personal Stigma Subscales and Social Distance Scale). RESULTS: The Personal Stigma subscale of 'Dangerous/unpredictable' was strongly positively correlated with participants' K10 psychological distress scores and strongly negatively correlated with years of education completed. There were moderate negative correlations between two Personal Stigma subscales ('Dangerous/unpredictable' and 'I-would-not-tell-anyone') and the length of stay in Australia. Being female was associated with an increase in personal stigma demonstrated by higher scores for 'I-would-not-tell-anyone' subscale than males. Similarly, increase in age was associated with a decrease on scores of the personal stigma 'Dangerous/unpredictable'. CONCLUSIONS: While future research with larger sample size are needed, the study findings can be considered as adding to the evidence base on mental illness related stigma in Arabic-speaking populations. Further, this study provides a starting point in developing the rationale for why population sub-group specific interventions are required to address mental illness stigma and improve MHL among Arabic-speaking refugee and migrant populations in Australia.

Associations of Sex, Age, and Cardiometabolic Risk Profiles With Brain Structure and Cognition: A UK Biobank Latent Class Analysis.

BACKGROUND AND OBJECTIVES: It is unknown whether there are sex-related profiles of cardiometabolic health that contribute differently to age-related changes in brain health during midlife. We studied how latent classes of middle-aged individuals clustering by age, sex, menopause, and cardiometabolic health were associated with brain structure and cognitive performance. METHODS: Health, brain, and abdominal MRI data from the UK Biobank cohort (men and women aged >40 years in the United Kingdom) were used. We applied latent class analysis to identify groups of individuals based on age, sex, menopausal status, and cardiometabolic health. We examined associations of class membership with brain volumes (total brain volume [TBV], gray matter volume [GMV], white matter volume [WMV], hippocampal volume, and white matter hyperintensity volume) and cognitive performance. RESULTS: Data were available for 36,420 individuals (mean age 64.9 years, 48.5% women). Eight latent classes differing in age, sex, and cardiometabolic risk were identified. Class 1 (reference class) included individuals with the lowest probability of older age and cardiometabolic risk, and the healthiest levels of brain volumes and cognition. In those aged >60 years, but not in those aged 50-60 years, the negative associations of age with TBV, GMV, and WMV were greater in the class comprising healthier older women than classes comprising older men of varying cardiometabolic and vascular health. There were no age-class interactions for cognitive test performance. DISCUSSION: Latent class analysis detected groups of middle-aged individuals clustering by cardiometabolic health. The relationship of age with brain volumes varies by sex, menopausal status, and cardiometabolic health profile.

The effect of antenatal pelvic floor muscle exercise on sexual function and labour and birth outcomes: A randomised controlled trial.

BACKGROUND: Pelvic floor muscle exercises (PFME) are recommended for treatment of urinary incontinence with less evidence available about the effect on female sexual function (FSF) and childbirth. AIM: To investigate the effect of antenatal PFME on FSF during pregnancy and the first three months following birth as a primary outcome, and on labour and birth outcomes as a secondary outcome. METHOD: 200 nulliparous women were randomised to control (n = 100) and intervention (n = 100) groups. The women in the intervention group (IG) undertook PFME from 20 weeks gestation until birth and had routine antenatal care, while those in the control group (CG) received routine antenatal care only. The Female Sexual Function Index (FSFI) was used to measure FSF at 36 weeks gestation and three months postnatal. Baseline characteristics and childbirth data were also collected and analysed using SPSS. RESULTS: There were no statistically significant differences between the two groups in terms of FSF scores during pregnancy and on childbirth outcomes. Sexual satisfaction was slightly higher in the CG [Mean ± SD, CG: 4.35 ± 1.45 vs. IG: 3.70 ± 1.50, (P = 0.03)] at three months after birth. However, 50% of women adhered to the PFME, and 40% of women did not resume sex by three months after the birth. CONCLUSION: Though some trends were observed, the results showed no effect of PFME on sexual function or labour and birth outcomes. This needs to be interpreted considering the 50% adherence to PFME. More research is recommended.

Mental Illness Stigma and Associated Factors among Arabic-Speaking Religious and Community Leaders.

Evidence suggests that Arabic-speaking refugees in Australia seek help from informal sources, including religious and community leaders, when experiencing mental health issues. Despite their significant influence, there is scarce research exploring attitudes of Arabic-speaking leaders toward mental illness. The current exploratory study explored mental illness stigma and various factors among Arabic-speaking religious and community leaders. This study uses a subset of data from an evaluation trial of mental health literacy training for Arabic-speaking religious and community leaders. Our dataset contains the pre-intervention survey responses for 52 Arabic-speaking leaders (69.2% female; mean age = 47.1, SD = 15.3) on the ability to recognise a mental disorder, beliefs about causes for developing mental illness, and two stigma measures, personal stigma, and social distance. Being female was associated with a decrease in personal stigma. An increase in age was associated with an increase in personal stigma. Correct recognition of a mental disorder was associated with decreased personal stigma, and after adjusting for age and gender, significance was retained for the I-would-not-tell-anyone subscale. Endorsing the cause "being a person of weak character" was associated with an increase in personal stigma. There is an urgent need for future research to elucidate stigma to develop effective educational initiatives for stigma reduction among Arabic-speaking leaders.

Apolipoproteins L1-6 share key cation channel-regulating residues but have different membrane insertion and ion conductance properties.

The human apolipoprotein L gene family encodes the apolipoprotein L1-6 (APOL1-6) proteins, which are effectors of the innate immune response to viruses, bacteria and protozoan parasites. Due to a high degree of similarity between APOL proteins, it is often assumed that they have similar functions to APOL1, which forms cation channels in planar lipid bilayers and membranes resulting in cytolytic activity. However, the channel properties of the remaining APOL proteins have not been reported. Here, we used transient overexpression and a planar lipid bilayer system to study the function of APOL proteins. By measuring lactate dehydrogenase release, we found that APOL1, APOL3, and APOL6 were cytolytic, whereas APOL2, APOL4, and APOL5 were not. Cells expressing APOL1 or APOL3, but not APOL6, developed a distinctive swollen morphology. In planar lipid bilayers, recombinant APOL1 and APOL2 required an acidic environment for the insertion of each protein into the membrane bilayer to form an ion conductance channel. In contrast, recombinant APOL3, APOL4, and APOL5 readily inserted into bilayers to form ion conductance at neutral pH, but required a positive voltage on the side of insertion. Despite these differences in membrane insertion properties, the ion conductances formed by APOL1-4 were similarly pH-dependent and cation-selective, consistent with conservation of the pore-lining region in each protein. Thus, despite structural conservation, the APOL proteins are functionally different. We propose that these proteins interact with different membranes and under different voltage and pH conditions within a cell to effect innate immunity to different microbial pathogens.

Coiled-coil binding of the leucine zipper domains of APOL1 is necessary for the open cation channel conformation.

Apolipoprotein L-I (APOL1) is a channel-forming effector of innate immunity. The common human APOL1 variant G0 provides protection against infection with certain Trypanosoma and Leishmania parasite species, but it cannot protect against the trypanosomes responsible for human African trypanosomiasis. Human APOL1 variants G1 and G2 protect against human-infective trypanosomes but also confer a higher risk of developing chronic kidney disease. Trypanosome-killing activity is dependent on the ability of APOL1 to insert into membranes at acidic pH and form pH-gated cation channels. We previously mapped the channel's pore-lining region to the C-terminal domain (residues 332-398) and identified a membrane-insertion domain (MID, residues 177-228) that facilitates acidic pH-dependent membrane insertion. In this article, we further investigate structural determinants of cation channel formation by APOL1. Using a combination of site-directed mutagenesis and targeted chemical modification, our data indicate that the C-terminal heptad-repeat sequence (residues 368-395) is a bona fide leucine zipper domain (ZIP) that is required for cation channel formation as well as lysis of trypanosomes and mammalian cells. Using protein-wide cysteine-scanning mutagenesis, coupled with the substituted cysteine accessibility method, we determined that, in the open channel state, both the N-terminal domain and the C-terminal ZIP domain are exposed on the intralumenal/extracellular side of the membrane and provide evidence that each APOL1 monomer contributes four transmembrane domains to the open cation channel conformation. Based on these data, we propose an oligomeric topology model in which the open APOL1 cation channel is assembled from the coiled-coil association of C-terminal ZIP domains.

Lifetime Corneal Edema Load Model.

Purpose: To highlight the potential benefits for long-term use of silicone hydrogels daily disposable (DD) contact lenses, particularly with patients who are noncompliant, sleeping or napping while wearing their lenses, or those who have higher oxygen demands and wear this modality for decades. Methods: Published data for corneal swelling with lenses and no lens wear were used to develop a nonlinear least squares model. The edema load experienced with a range of oxygen transmissibilities (Dk/t) and wear compliance (sleep and napping) was determined. A mixed-effects linear regression model was used to compare the edema load for high and average corneal swellers. Results: The edema load generated demonstrates that a high Dk/t silicone hydrogel lens results in edema levels close to that with no lens wear. In comparison, hydrogels with a Dk/t of 27 (× 10-9 [cm mL{O2}][s mL mm Hg]), worn on a daily wear schedule will result in 1.5 times more edema and up to two times more if the patient is noncompliant over each decade of wear. High swellers after four decades of wear will have an edema load 10 to 17 times greater than average swellers depending on Dk/t and their degree of noncompliance with the daily wear modality. Conclusions: Prescribing silicone hydrogel DD lenses, particularly with higher DK/t, may help to maintain the long-term ocular health of patients, when they wear their lenses fulltime for many decades. Translational Relevance: Illustrates the importance of Dk/t for any CL wear modality where patients nap or sleep in lenses or have high oxygen needs.

A rare variant in EZH2 is associated with prostate cancer risk.

Prostate cancer (PrCa) is highly heritable, and although rare variants contribute significantly to PrCa risk, few have been identified to date. Herein, whole-genome sequencing was performed in a large PrCa family featuring multiple affected relatives spanning several generations. A rare, predicted splice site EZH2 variant, rs78589034 (G > A), was identified as segregating with disease in all but two individuals in the family, one of whom was affected with lymphoma and bowel cancer and a female relative. This variant was significantly associated with disease risk in combined familial and sporadic PrCa datasets (n = 1551; odds ratio [OR] = 3.55, P = 1.20 × 10-5 ). Transcriptome analysis was performed on prostate tumour needle biopsies available for two rare variant carriers and two wild-type cases. Although no allele-dependent differences were detected in EZH2 transcripts, a distinct differential gene expression signature was observed when comparing prostate tissue from the rare variant carriers with the wild-type samples. The gene expression signature comprised known downstream targets of EZH2 and included the top-ranked genes, DUSP1, FOS, JUNB and EGR1, which were subsequently validated by qPCR. These data provide evidence that rs78589034 is associated with increased PrCa risk in Tasmanian men and further, that this variant may be associated with perturbed EZH2 function in prostate tissue. Disrupted EZH2 function is a driver of tumourigenesis in several cancers, including prostate, and is of significant interest as a therapeutic target.

Deletions in VANGL1 are a risk factor for antibody-mediated kidney disease.

We identify an intronic deletion in VANGL1 that predisposes to renal injury in high risk populations through a kidney-intrinsic process. Half of all SLE patients develop nephritis, yet the predisposing mechanisms to kidney damage remain poorly understood. There is limited evidence of genetic contribution to specific organ involvement in SLE.1,2 We identify a large deletion in intron 7 of Van Gogh Like 1 (VANGL1), which associates with nephritis in SLE patients. The same deletion occurs at increased frequency in an indigenous population (Tiwi Islanders) with 10-fold higher rates of kidney disease compared with non-indigenous populations. Vangl1 hemizygosity in mice results in spontaneous IgA and IgG deposition within the glomerular mesangium in the absence of autoimmune nephritis. Serum transfer into B cell-deficient Vangl1+/- mice results in mesangial IgG deposition indicating that Ig deposits occur in a kidney-intrinsic fashion in the absence of Vangl1. These results suggest that Vangl1 acts in the kidney to prevent Ig deposits and its deficiency may trigger nephritis in individuals with SLE.

Interactions Between Age, Sex, Menopause, and Brain Structure at Midlife: A UK Biobank Study.

OBJECTIVES: Age and female sex are risk factors for dementia, and menopause is associated with cognitive dysfunction. Previous work largely considered the effects of sex and menopause as being independent of age. We studied whether age interacts with sex or menopause in explaining imaging biomarkers of dementia during midlife. METHODS: In this cross-sectional study of UK Biobank participants with brain magnetic resonance imaging (MRI), we explored the interaction of age with sex or menopausal status in explaining total brain volume (TBV), gray matter volume (GMV), white matter volume (WMV), white matter hyperintensity volume (WMHV), regional cortical volume , and subcortical volume. RESULTS: Data were available for 1827 postmenopausal women, 230 pre/perimenopausal women and 2165 men (median age 63.3 years). There was a significant interaction between age and sex (P = .024) for TBV, where the inverse association age with TBV was steeper in women (ß = -5.35 mL/year) than in men (ß = -4.77 mL/year). Similar age-sex interactions were also observed for GMV and WMV. In women, there was a significant interaction between age and menopausal status (P = .007) where the inverse association of age with TBV was steeper in postmenopausal (ß = -5.89 mL/year) than in pre/perimenopausal women (ß = -1.61 mL/year). Similar age-menopause interactions were found in predicting lower GMV and higher WMHV. Differences in the direction of these age-sex and age-menopause interactions were found for regional cortical and subcortical brain volumes. CONCLUSION: Sex and menopause both interact with age during midlife in explaining MRI biomarkers of dementia. Further work is required to understand the mechanisms driving these interactions to develop strategies for delaying dementia.

Cerebral small vessel disease genomics and its implications across the lifespan.

White matter hyperintensities (WMH) are the most common brain-imaging feature of cerebral small vessel disease (SVD), hypertension being the main known risk factor. Here, we identify 27 genome-wide loci for WMH-volume in a cohort of 50,970 older individuals, accounting for modification/confounding by hypertension. Aggregated WMH risk variants were associated with altered white matter integrity (p = 2.5×10-7) in brain images from 1,738 young healthy adults, providing insight into the lifetime impact of SVD genetic risk. Mendelian randomization suggested causal association of increasing WMH-volume with stroke, Alzheimer-type dementia, and of increasing blood pressure (BP) with larger WMH-volume, notably also in persons without clinical hypertension. Transcriptome-wide colocalization analyses showed association of WMH-volume with expression of 39 genes, of which four encode known drug targets. Finally, we provide insight into BP-independent biological pathways underlying SVD and suggest potential for genetic stratification of high-risk individuals and for genetically-informed prioritization of drug targets for prevention trials.

Multiple lifestyle factors and depressed mood: a cross-sectional and longitudinal analysis of the UK Biobank (N = 84,860).

BACKGROUND: There is now evolving data exploring the relationship between depression and various individual lifestyle factors such as diet, physical activity, sleep, alcohol intake, and tobacco smoking. While this data is compelling, there is a paucity of longitudinal research examining how multiple lifestyle factors relate to depressed mood, and how these relations may differ in individuals with major depressive disorder (MDD) and those without a depressive disorder, as 'healthy controls' (HC). METHODS: To this end, we assessed the relationships between 6 key lifestyle factors (measured via self-report) and depressed mood (measured via a relevant item from the Patient Health Questionnaire) in individuals with a history of or current MDD and healthy controls (HCs). Cross-sectional analyses were performed in the UK Biobank baseline sample, and longitudinal analyses were conducted in those who completed the Mental Health Follow-up. RESULTS: Cross-sectional analysis of 84,860 participants showed that in both MDD and HCs, physical activity, healthy diet, and optimal sleep duration were associated with less frequency of depressed mood (all p < 0.001; ORs 0.62 to 0.94), whereas screen time and also tobacco smoking were associated with higher frequency of depressed mood (both p < 0.0001; ORs 1.09 to 1.36). In the longitudinal analysis, the lifestyle factors which were protective of depressed mood in both MDD and HCs were optimal sleep duration (MDD OR = 1.10; p < 0.001, HC OR = 1.08; p < 0.001) and lower screen time (MDD OR = 0.71; p < 0.001, HC OR = 0.80; p < 0.001). There was also a significant interaction between healthy diet and MDD status (p = 0.024), while a better-quality diet was indicated to be protective of depressed mood in HCs (OR = 0.92; p = 0.045) but was not associated with depressed mood in the MDD sample. In a cross-sectional (OR = 0.91; p < 0.0001) analysis, higher frequency of alcohol consumption was surprisingly associated with reduced frequency of depressed mood in MDD, but not in HCs. CONCLUSIONS: Our data suggest that several lifestyle factors are associated with depressed mood, and in particular, it calls into consideration habits involving increased screen time and a poor sleep and dietary pattern as being partly implicated in the germination or exacerbation of depressed mood.

Cation channel conductance and pH gating of the innate immunity factor APOL1 are governed by pore-lining residues within the C-terminal domain.

The human innate immunity factor apolipoprotein L-I (APOL1) protects against infection by several protozoan parasites, including Trypanosoma brucei brucei Endocytosis and acidification of high-density lipoprotein-associated APOL1 in trypanosome endosomes leads to eventual lysis of the parasite due to increased plasma membrane cation permeability, followed by colloid-osmotic swelling. It was previously shown that recombinant APOL1 inserts into planar lipid bilayers at acidic pH to form pH-gated nonselective cation channels that are opened upon pH neutralization. This corresponds to the pH changes encountered during endocytic recycling, suggesting APOL1 forms a cytotoxic cation channel in the parasite plasma membrane. Currently, the mechanism and domains required for channel formation have yet to be elucidated, although a predicted helix-loop-helix (H-L-H) was suggested to form pores by virtue of its similarity to bacterial pore-forming colicins. Here, we compare recombinant human and baboon APOL1 orthologs, along with interspecies chimeras and individual amino acid substitutions, to identify regions required for channel formation and pH gating in planar lipid bilayers. We found that whereas neutralization of glutamates within the H-L-H may be important for pH-dependent channel formation, there was no evidence of H-L-H involvement in either pH gating or ion selectivity. In contrast, we found two residues in the C-terminal domain, tyrosine 351 and glutamate 355, that influence pH gating properties, as well as a single residue, aspartate 348, that determines both cation selectivity and pH gating. These data point to the predicted transmembrane region closest to the APOL1 C terminus as the pore-lining segment of this novel channel-forming protein.

Improving the mental wellbeing of Arabic speaking refugees: an evaluation of a mental health promotion program.

BACKGROUND: Refugee populations have particularly high rates of mental health problems, including Posttraumatic Stress Disorder (PTSD) and depression. However, uptake of mental health care may be low even when severe depression and PTSD symptoms are present in individuals following resettlement. This is likely due, at least in part, to cultural influences on refugees' knowledge and beliefs about mental health problems and their treatment. We sought to provide preliminary evidence for the effectiveness of a culturally tailored mental health promotion program for Arabic-speaking refugees. METHODS: A total of 33 Arabic-speaking refugees resettled in South Western Sydney were recruited and completed intervention which consisted of weekly three-hour sessions for 4 weeks delivered in Arabic. Key aspects of mental health literacy, help-seeking intentions and levels of general psychological distress were assessed, by means of a self-report survey, pre-intervention, (immediately) post-intervention and 3 months following intervention. RESULTS: Of the 33 participants that completed the intervention, 31 completed the immediate post-intervention survey and 29 completed the 3 months follow-up survey. Improvements in most aspects of mental health literacy assessed were found immediately post-intervention and at follow-up, although only changes relating to stigmatising attitudes were statistically significant. Additionally, a statistically significant decrease in participants' levels of general psychological distress was observed immediately following the intervention, and this decrease was sustained at follow-up. CONCLUSION: While further research employing a more rigorous study design and larger sample size will be needed, results of this initial trial suggest that a culturally tailored mental health promotion program targeting key aspects of mental health literacy can improve the mental health of Arabic-speaking refugees resettled in a Western nation.

Analysis of the F2LR3 (PAR4) Single Nucleotide Polymorphism (rs773902) in an Indigenous Australian Population.

The F2RL3 gene encoding protease activated receptor 4 (PAR4) contains a single nucleotide variant, rs773902, that is functional. The resulting PAR4 variants, Thr120, and Ala120, are known to differently affect platelet reactivity to thrombin. Significant population differences in the frequency of the allele indicate it may be an important determinant in the ethnic differences that exist in thrombosis and hemostasis, and for patient outcomes to PAR antagonist anti-platelet therapies. Here we determined the frequency of rs773902 in an Indigenous Australian group comprising 467 individuals from the Tiwi Islands. These people experience high rates of renal disease that may be related to platelet and PAR4 function and are potential recipients of PAR-antagonist treatments. The rs773902 minor allele frequency (Thr120) in the Tiwi Islanders was 0.32, which is similar to European and Asian groups and substantially lower than Melanesians and some African groups. Logistic regression and allele distortion testing revealed no significant associations between the variant and several markers of renal function, as well as blood glucose and blood pressure. These findings suggest that rs773902 is not an important determinant for renal disease in this Indigenous Australian group. However, the relationships between rs773902 genotype and platelet and drug responsiveness in the Tiwi, and the allele frequency in other Indigenous Australian groups should be evaluated.

Apolipoprotein L-1 renal risk variants form active channels at the plasma membrane driving cytotoxicity.

Recently evolved alleles of Apolipoprotein L-1 (APOL1) provide increased protection against African trypanosome parasites while also significantly increasing the risk of developing kidney disease in humans. APOL1 protects against trypanosome infections by forming ion channels within the parasite, causing lysis. While the correlation to kidney disease is robust, there is little consensus concerning the underlying disease mechanism. We show in human cells that the APOL1 renal risk variants have a population of active channels at the plasma membrane, which results in an influx of both Na+ and Ca2+. We propose a model wherein APOL1 channel activity is the upstream event causing cell death, and that the activate-state, plasma membrane-localized channel represents the ideal drug target to combat APOL1-mediated kidney disease.

Inducible Germline IgMs Bridge Trypanosome Lytic Factor Assembly and Parasite Recognition.

Trypanosomiasis is a devastating neglected tropical disease affecting livestock and humans. Humans are susceptible to two Trypanosoma brucei subspecies but protected from other trypanosomes by circulating high-density lipoprotein (HDL) complexes called trypanosome lytic factors (TLFs) 1 and 2. TLFs contain apolipoprotein L-1 contributing to lysis and haptoglobin-related protein (HPR), which can function as a ligand for a parasite receptor. TLF2 also uniquely contains non-covalently associated immunoglobin M (IgM) antibodies, the role and origin of which remain unclear. Here, we show that these TLF2-associated IgMs interact with both HPR and alternate trypanosome surface proteins, including variant surface glycoprotein, likely facilitating complex biogenesis and TLF uptake into parasites. TLF2-IgMs are germline antibodies that, while present at basal concentrations in healthy individuals, are elicited by trypanosome infection in both murine models and human sleeping sickness patients. These data suggest that poly- and self-reactive germline antibodies such as TLF2-associated IgMs play a role in antimicrobial immunity.

All You Ever Wanted to Know About APOL1 and TLFs and Did Not Dare Ask.

Interest in trypanosome lytic factors (TLFs) and apolipoprotein L1, the ion channel-forming protein component of TLFs, has increased tenfold since 2010. This is due to the association of African variants of APOL1 with kidney disease such that interest has reached circles beyond parasitology. We have extensive experience purifying and working with these proteins and protein complexes. Herein we describe our detailed purification protocols to aid the new burgeoning field by providing an opportunity for consistency in reagents used across laboratories. We emphasize that it is imperative to maintain APOL1 protein intact (~42 kDa) to analyze the active ion channel-forming component/protein.