👤 Blair W MacLeod

An accurate understanding of prognosis in Parkinson's disease (PD) is important for patient information provision, personalized treatment, and clinical trial design, but most previous research has been biased towards younger, healthier patients. To describe key clinical outcomes longitudinally and identify baseline prognostic factors (predictors) for these outcomes using population-representative PD cohorts. We meta-analyzed individual patient data from six incidence cohorts in Western Europe (Norway, Sweden, and UK). Each cohort aimed to recruit and follow up all newly diagnosed cases in defined population/incidence periods (between 2000 and 2011). We described postural instability (Hoehn & Yahr Stage 3), functional dependency (needing help with daily activities), dementia, and death with up to 12 years' follow-up and investigated clinical and genetic predictors using frailty Cox models. In 883 population-based incident patients, median age at motor symptom onset was 69.2 years. Median time to postural instability and functional dependency was 7.4 years. Dementia affected 49.6% by 10 years and 54.7% had died by 12 years (median survival 9.4 years). Older age, higher Movement Disorder Society-Unified Parkinson's Disease Rating Scale-Part III (MDS-UPDRS-III) score, and lower Mini-Mental State Examination (MMSE) were significantly associated with all outcomes; cognitive symptoms and GBA polymorphisms with each outcome except mortality; and APOE ε4 with increased mortality and dementia. This first individual patient data meta-analysis of population-based incidence cohorts provides robust prognostic data, with fewer selection biases than previous PD studies, for informing people with PD about prognosis. In incidence cohorts, overall PD prognosis is worse than previously suggested, with key outcomes often occurring early. Further work should develop validated prognostic models for objective stratification of prognostic risk and for personalized medicine. © 2026 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. Show less

Dairy cattle, particularly in Australia where dairy farming is predominantly pasture based, are experiencing an increased incidence of heat stress through rising global temperatures, causing a detrimental impact on productivity and welfare. Improving the thermotolerance of dairy cows through genetic selection is a potential proactive solution for mitigating the impact of heat stress for the dairy industry. Although heat tolerance breeding values for milk yield traits have been available to Australian dairy producers since 2017, considerable potential remains to develop genetic evaluation for heat tolerance of fertility and understanding of the underlying genetic architecture for heat tolerance. The objective of this study was to investigate the effect of heat stress measured as temperature and humidity index (THI) on fertility traits and to identify genomic regions associated with heat tolerance in 2 specific fertility traits: first service non-return rate (FNRR) and successful calving rate to first service (SCRFS). In this study, we assembled more than 892k phenotypic records of Holstein cows with THI and fertility traits and identified specific periods with respect to service day. The effect of heat stress on fertility was assessed using random regression (RR) sire model for estimating the change in genetic variance of fertility across various THI and obtaining heat tolerance solution (slope) for sires. Also, whole genome sequence genome-wide association studies (GWAS) were undertaken based on heat tolerance phenotypes of 5k Holstein bulls with at least 10 daughters with fertility data. The assessment of the different THI definitions based on different numbers of days before and after artificial service days on the fertility traits showed that the most prominent effect of THI on fertility outcomes was observed for THI 7 d preceding service (including the service day) and 6 d after service day. Heat tolerance (HT) traits with respect to FNRR and SCRFS are lowly heritable and ranged from 0.01 to 0.04 under moderate THI conditions ranging between 60 and 70. However, as the THI exceeded 70, the heritability increased to up to 0.08, indicating increased genetic variance as THI increased. Genetic correlations between extreme THI ranges were as low as 0.13, while correlations between consecutive THI ranges reached up to 0.98. This finding suggests the presence of genotype by environment interactions due to heat stress. Notable variation in heat stress sensitivity among sires was also observed for HT fertility. In total, 553 sequence variants were significantly associated HT fertility, and 52 of them were identified as independent QTL. Some of QTL regions were located near or within the genes that are involved in oxidative stress, inflammation, and fertility (e.g., TRPC5, CDK5RAP2, MGAT1, COMMD10, PRR7, GRK6, CUGBP1, MAFG, HERC2, NAPRT, HSD17B12, THRB, and EEF1D). The findings in this study will further aid in understanding genetic architecture and provide valuable information for improving the accuracy of genomic prediction of heat tolerance in dairy cattle. Show less

The omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have numerous benefits, including strong anti-inflammatory and triglyceride-lowering properties. EPA and DHA are primarily obtained by consuming fatty fish; however, they are also endogenously synthesized primarily in the liver from α-linolenic acid (ALA) through a pathway mediated by the delta-6 desaturase (D6D) enzyme. Previous reports in rodents and humans suggest that dietary proteins such as soy and dairy may impact this pathway differently. The primary aim was to investigate the effects of diets containing either soy or milk protein on the expression, abundance, and enzymatic activity of the desaturases and elongases regulating hepatic omega-3 fatty acid biosynthesis. Male C57BL/6N mice (n = 16 per group) were fed a moderate-fat diet for 8 weeks containing either 1% or 3% energy from ALA. Protein content (15% energy) corresponded to either skim milk powder (SMP) or soy protein isolate (SPI). Hepatic fatty acid content was quantified by gas chromatography-flame ionization detection. Gene expression and protein expression were assessed by RT-qPCR and western blotting, respectively. D6D activity was measured in isolated hepatic microsomes. Fat oxidation was examined using a high-resolution respirometer. Hepatic omega-3 fatty acids (ALA, SDA, EPA, DPAn-3) were lower in SPI-fed mice compared to SMP-fed mice. Fads1, Fads2, Elovl2, and Elovl5 expression was higher in SPI-fed mice compared to those fed SMP, while Srebp-1c expression was lower and Cpt1a expression higher in SPI-fed mice. Consistent with the changes seen at the gene expression levels, FADS2 protein abundance was higher in SPI-fed mice, whereas ELOVL5 protein expression was lower in the SPI groups. Little to no differences in microsomal D6D activity and mitochondrial respiration were detected. Our findings suggest that SPI-related reductions in hepatic omega-3 fatty acid content occur independent of changes in desaturase gene expression, protein expression, enzymatic activity, or mitochondrial respiration. Further studies investigating the influence of dietary proteins on ALA metabolism are therefore warranted. Show less

Halting breast cancer metastatic relapse following primary tumor removal remains challenging due to a lack of specific vulnerabilities to target during the clinical dormancy phase. To identify such vulnerabilities, we conducted genome-wide CRISPR screens on two breast cancer cell lines with distinct dormancy properties: 4T1 (short-term dormancy) and 4T07 (prolonged dormancy). The dormancy-prone 4T07 cells displayed a unique dependency on class III PI3K (PIK3C3). Unexpectedly, 4T07 cells exhibited higher mechanistic target of rapamycin complex 1 (mTORC1) activity than 4T1 cells due to lysosome-dependent signaling occurring at the cell periphery. Pharmacologic inhibition of PIK3C3 suppressed this phenotype in the 4T1-4T07 models as well as in human breast cancer cell lines and a breast cancer patient-derived xenograft. Furthermore, inhibiting PIK3C3 selectively reduced metastasis burden in the 4T07 model and eliminated dormant cells in a HER2-dependent murine breast cancer dormancy model. These findings suggest that PIK3C3-peripheral lysosomal signaling to mTORC1 may represent a targetable axis for preventing dormant cancer cell-initiated metastasis in patients with breast cancer. Dormancy-prone breast cancer cells depend on the class III PI3K to mediate peripheral lysosomal positioning and mTORC1 hyperactivity, which can be targeted to blunt breast cancer metastasis. Show less

The production of the omega-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from alpha-linolenic acid (ALA) relies on the delta-6 desaturase (D6D) enzyme encoded by the Fads2 gene. While EPA and DHA reduce hepatic triacylglycerol (TAG) storage and regulate lipogenesis, the independent impact of ALA is less understood. To address this gap in knowledge, hepatic fatty acid metabolism was investigated in male wild-type (WT) and Fads2 knockout (KO) mice fed diets (16% kcal from fat) containing either lard (no n-3 LCPUFA), flaxseed oil (ALA-rich), or menhaden oil (EPA/DHA rich) for 21 weeks. Fat content and composition, as well as markers of lipogenesis, glyceroneogenesis, and TAG synthesis, were analyzed using histology, gas chromatography, and reverse transcription quantitative PCR (RT-qPCR). Mice fed the menhaden diet had significantly lower hepatic TAG compared to both lard- and flax-fed mice, concomitant with changes in n-3 and n-6 LCPUFA in both TAG and phospholipid (PL) fractions (all P < 0.05). Flax-fed WT mice had lower liver TAG content compared to their KO counterparts. Menhaden-fed mice had significantly lower expression of key lipogenic (Scd1, Srebp-1c, Fasn, Fads1, and Fads2), glyceroneogenic (Pck1), and TAG synthesis (Agpat3) genes compared to lard, with flax-fed mice showing some intermediate effects. Gene expression effects were independent of D6D activity, since no differences were detected between WT and KO mice fed the same diet. This study demonstrates that EPA/DHA and not ALA itself is critical for the prevention of hepatic steatosis. Show less

Halting breast cancer metastatic relapses following primary tumor removal and the clinical dormant phase, remains challenging, due to a lack of specific vulnerabilities to target during dormancy. To address this, we conducted genome-wide CRISPR screens on two breast cancer cell lines with distinct dormancy properties: 4T1 (short-term dormancy) and 4T07 (prolonged dormancy). We discovered that loss of class-III PI3K, Pik3c3, revealed a unique vulnerability in 4T07 cells. Surprisingly, dormancy-prone 4T07 cells exhibited higher mTORC1 activity than 4T1 cells, due to lysosome-dependent signaling occurring at the cell periphery. Pharmacological inhibition of Pik3c3 counteracted this phenotype in 4T07 cells, and selectively reduced metastasis burden only in the 4T07 dormancy-prone model. This mechanism was also detected in human breast cancer cell lines in addition to a breast cancer patient-derived xenograft supporting that it may be relevant in humans. Our findings suggest dormant cancer cell-initiated metastasis may be prevented in patients carrying tumor cells that display PIK3C3-peripheral lysosomal signaling to mTORC1. We reveal that dormancy-prone breast cancer cells depend on the class III PI3K to mediate a constant peripheral lysosomal positioning and mTORC1 hyperactivity. Targeting this pathway might blunt breast cancer metastasis. Show less

Aged skin is prone to viral infections, but the mechanisms responsible for this immunosenescent immune risk are unclear. We observed that aged murine and human skin expressed reduced levels of antiviral proteins (AVPs) and circadian regulators, including Bmal1 and Clock. Bmal1 and Clock were found to control rhythmic AVP expression in skin, and such circadian control of AVPs was diminished by disruption of immune cell IL-27 signaling and deletion of Bmal1/Clock genes in mouse skin, as well as siRNA-mediated knockdown of CLOCK in human primary keratinocytes. We found that treatment with the circadian-enhancing agents nobiletin and SR8278 reduced infection of herpes simplex virus 1 in epidermal explants and human keratinocytes in a BMAL1/CLOCK-dependent manner. Circadian-enhancing treatment also reversed susceptibility of aging murine skin and human primary keratinocytes to viral infection. These findings reveal an evolutionarily conserved and age-sensitive circadian regulation of cutaneous antiviral immunity, underscoring circadian restoration as an antiviral strategy in aging populations. Show less

Aged skin is prone to viral infections, but the mechanisms responsible for this immunosenescent immune risk are unclear. We observed that aged murine and human skin expressed reduced antiviral proteins (AVPs) and circadian regulators including Bmal1 and Clock. Bmal1 and Clock were found to control rhythmic AVP expression in skin and such circadian-control of AVPs was diminished by disruption of immune cell interleukin 27 signaling and deletion of Bmal1/Clock genes in mouse skins, as well as siRNA-mediated knockdown of CLOCK in human primary keratinocytes. We found that treatment of circadian enhancing agents, nobiletin and SR8278, reduced infection of herpes simplex virus 1 (HSV1) in epidermal explants and human keratinocytes in a Bmal1/Clock-dependent manner. Circadian enhancing treatment also reversed susceptibility of aging murine skin and human primary keratinocytes to viral infection. These findings reveal an evolutionarily conserved and age-sensitive circadian regulation of cutaneous antiviral immunity, underscoring circadian restoration as an antiviral strategy in aging populations. Show less

The skin serves as the interface between the body and the environment and plays a fundamental role in innate antimicrobial host immunity. Antiviral proteins (AVPs) are part of the innate host defense system and provide protection against viral pathogens. How breach of the skin barrier influences innate AVP production remains largely unknown. In this study, we characterized the induction and regulation of AVPs after skin injury and identified a key role of TRPV1 in this process. Transcriptional and phenotypic profiling of cutaneous wounds revealed that skin injury induces high levels of AVPs in both mice and humans. Remarkably, pharmacologic and genetic ablation of TRPV1-mediated nociception abrogated the induction of AVPs, including Oas2, Oasl2, and Isg15 after skin injury in mice. Conversely, stimulation of TRPV1 nociceptors was sufficient to induce AVP production involving the CD301b Show less

Crosstalk between T cells, dendritic cells, and macrophages in temporal leukocyte clusters within barrier tissues provides a new concept for T cell activation in the skin. Activated T cells from these leukocyte clusters play critical roles in the efferent phase of allergic contact hypersensitivity (CHS). However, the cytokines driving maintenance and survival of pathogenic T cells during and following CHS remain mostly unknown. Upon epicutaneous allergen challenge, we here report that macrophages produce IL-27 which then induces IL-15 production from epidermal keratinocytes and dermal myeloid cells within leukocyte clusters. In agreement with the known role of IL-15 as a T cell survival factor and growth cytokine, this signaling axis enhances BCL2 and survival of skin T cells. Genetic depletion or pharmacological blockade of IL-27 in CHS mice leads to abrogated epidermal IL-15 production resulting in a decrease in BCL2 expression in T cells and a decline in dermal CD8 Show less

UVR and immunosuppression are major risk factors for cutaneous squamous cell carcinoma (cSCC). Regulatory T cells promote cSCC carcinogenesis, and in other solid tumors, infiltrating regulatory T cells and CD8 Show less

In the skin, antiviral proteins and other immune molecules serve as the first line of innate antiviral defense. Here, we identify and characterize the induction of cutaneous innate antiviral proteins in response to IL-27 and its functional role during cutaneous defense against Zika virus infection. Transcriptional and phenotypic profiling of epidermal keratinocytes treated with IL-27 demonstrated activation of antiviral proteins OAS1, OAS2, OASL, and MX1 in the skin of both mice and humans. IL-27-mediated antiviral protein induction was found to occur in a STAT1- and IRF3-dependent but STAT2-independent manner. Moreover, using IL27ra mice, we demonstrate a significant role for IL-27 in inhibiting Zika virus morbidity and mortality following cutaneous, but not intravenous, inoculation. Together, our results demonstrate a critical and previously unrecognized role for IL-27 in cutaneous innate antiviral immunity against Zika virus. Show less

mRNA processing, transport, translation, and ultimately degradation involve a series of dedicated protein complexes that often assemble into large membraneless structures such as stress granules (SGs) and processing bodies (PBs). Here, systematic in vivo proximity-dependent biotinylation (BioID) analysis of 119 human proteins associated with different aspects of mRNA biology uncovers 7424 unique proximity interactions with 1,792 proteins. Classical bait-prey analysis reveals connections of hundreds of proteins to distinct mRNA-associated processes or complexes, including the splicing and transcriptional elongation machineries (protein phosphatase 4) and the CCR4-NOT deadenylase complex (CEP85, RNF219, and KIAA0355). Analysis of correlated patterns between endogenous preys uncovers the spatial organization of RNA regulatory structures and enables the definition of 144 core components of SGs and PBs. We report preexisting contacts between most core SG proteins under normal growth conditions and demonstrate that several core SG proteins (UBAP2L, CSDE1, and PRRC2C) are critical for the formation of microscopically visible SGs. Show less

Controversy exists on the benefits versus harms of n-6 polyunsaturated fatty acids (n-6 PUFA). Although n-6 PUFA demonstrates anti-atherosclerotic properties, survival following cardiac remodeling may be compromised. We hypothesized that n-6 PUFA like linoleic acid (LA) or other downstream PUFAs like γ-linolenic acid or arachidonic acid alter the transforming growth factor-β (TGFβ)-collagen axis in the heart. Excess dietary LA increased the collagen I/III ratio in the mouse myocardium, leading to cardiac "stiffening" characterized by impaired transmitral flow indicative of early diastolic dysfunction within 5 weeks. In vitro, LA under TGFβ1 stimulation increased collagen I and lysyl oxidase (LOX), the enzyme that cross-links soluble collagen resulting in deposited collagen. Overexpression of fatty acid desaturase 2 (fads2), which metabolizes LA to downstream PUFAs, reduced collagen deposits, LOX maturation, and activity with LA, whereas overexpressing fads1, unrelated to LA desaturation, did not. Furthermore, fads2 knockdown by RNAi elevated LOX activity and collagen deposits in fibroblasts with LA but not oleic acid, implying a buildup of LA for aggravating such pro-fibrotic effects. As direct incubation with γ-linolenic acid or arachidonic acid also attenuated collagen deposits and LOX activity, we concluded that LA itself, independent of other downstream PUFAs, promotes the pro-fibrotic effects of n-6 PUFA. Overall, these results attempt to reconcile opposing views of n-6 PUFA on the cardiovascular system and present evidence supporting a cardiac muscle-specific effect of n-6 PUFAs. Therefore, aggravation of the collagen I/III ratio and cardiac stiffening by excess n-6 PUFA represent a novel pathway of cardiac lipotoxicity caused by high n-6 PUFA diets. Show less