Background: Amyotrophic lateral sclerosis (ALS) is a fatal, progressive neurogenerative disease caused by combined genetic susceptibilities and environmental exposures. Identifying and validating these exposures are of paramount importance to modify disease risk. We previously reported that persistent organic pollutants (POPs) associate with ALS risk and survival and aimed to replicate these findings in a new cohort.Method: Participants with and without ALS recruited in Michigan provided plasma samples for POPs analysis by isotope dilution with triple quadrupole mass spectrometry. ORs for risk models and hazard ratios for survival models were calculated for individual POPs. POP mixtures were represented by environmental risk scores (ERS), a summation of total exposures, to evaluate the association with risk (ERS^risk) and survival (ERS^survival).Results: Samples from 164 ALS and 105 control participants were analysed. Several individual POPs significantly associated with ALS, including 8 of 22 polychlorinated biphenyls and 7 of 10 organochlorine pesticides (OCPs). ALS risk was most strongly represented by the mixture effects of OCPs alpha-hexachlorocyclohexane, hexachlorobenzene,trans-nonachlor andcis-nonachlor and an interquartile increase in ERS^riskenhanced ALS risk 2.58 times (p<0.001). ALS survival was represented by the combined mixture of all POPs and an interquartile increase in ERS^survivalenhanced ALS mortality rate 1.65 times (p=0.008).Conclusions: These data continue to support POPs as important factors for ALS risk and progression and replicate findings in a new cohort. The assessments of POPs in non-Michigan ALS cohorts are encouraged to better understand the global effect and the need for targeted disease risk reduction strategies.

Objective: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by altered metabolome and energy homeostasis, manifesting with body mass index changes and hypermetabolism—both prognostic of disease progression and survival. The cross‐sectional ALS metabolome has been characterized, but longitudinal correlations to functional decline are lacking.Methods: We longitudinally evaluated metabolomes from ALS plasma and terminal postmortem spinal cord and brain motor cortex tissue. We constructed 3 plasma models. A linear mixed effects model correlated all metabolite levels across all timepoints to their corresponding functional scores. An interaction model predicted a longitudinal change in function from baseline metabolites, whereas a progression model identified metabolites linked to a 20% or 50% drop in function. In postmortem samples, differential metabolites in onset versus second spinal cord segments served as a surrogate of disease progression. Mendelian randomization assessed potential causality from metabolites.Results: In plasma, all models primarily selected lipid metabolites and sub‐pathways, in addition to amino acids, xenobiotics, and various less frequently selected pathways. Among lipids, fatty acids and sphingomyelins were predominant, along with plasmalogens, phosphatidylcholines, and lysophospholipids. Sex interaction findings were nominal. In the spinal cord, sphingomyelin and long‐chain saturated and monounsaturated fatty acids were more abundant in the onset segment tissue, whereas phosphatidylcholines and phosphatidylethanolamines were less abundant. Mendelian randomization suggested that impaired carnitine and short chain acylcarnitine metabolism may be genetically determined in ALS, along with various antioxidant derivatives.Interpretation: Our findings suggest metabolomic changes primarily involving different lipid classes and carnitine metabolism may underscore ALS severity and progression. ANN NEUROL 2025;98:19–34

Background The pathogenesis of amyotrophic lateral sclerosis (ALS) involves both genetic and environmental factors. This study investigates associations between metal measures in plasma and urine, ALS risk and survival and exposure sources. Methods Participants with and without ALS from Michigan provided plasma and urine samples for metal measurement via inductively coupled plasma mass spectrometry. ORs and HRs for each metal were computed using risk and survival models. Environmental risk scores (ERS) were created to evaluate the association between exposure mixtures and ALS risk and survival and exposure source. ALS (ALS-PGS) and metal (metal-PGS) polygenic risk scores were constructed from an independent genome-wide association study and relevant literature-selected single-nucleotide polymorphisms. Results Plasma and urine samples from 454 ALS and 294 control participants were analysed. Elevated levels of individual metals, including copper, selenium and zinc, significantly associated with ALS risk and survival. ERS representing metal mixtures strongly associated with ALS risk (plasma, OR=2.95, CI=2.38–3.62, p<0.001; urine, OR=3.10, CI=2.43–3.97, p<0.001) and poorer ALS survival (plasma, HR=1.37, CI=1.20–1.58, p<0.001; urine, HR=1.44, CI=1.23–1.67, p<0.001). Addition of the ALS-PGS or metal-PGS did not alter the significance of metals with ALS risk and survival. Occupations with high potential of metal exposure associated with elevated ERS. Additionally, occupational and non-occupational metal exposures were associated with measured plasma and urine metals. Conclusion Metals in plasma and urine associated with increased ALS risk and reduced survival, independent of genetic risk, and correlated with occupational and non-occupational metal exposures. These data underscore the significance of metal exposure in ALS risk and progression.

Patients with type 2 diabetes often develop the microvascular complications of diabetic kidney disease (DKD) and diabetic peripheral neuropathy (DPN), which decrease quality of life and increase mortality. Unfortunately, treatment options for DKD and DPN are limited. Lifestyle interventions, such as changes to diet, have been proposed as non‐pharmacological treatment options for preventing or improving DKD and DPN. However, there are no reported studies simultaneously evaluating the therapeutic efficacy of varying dietary interventions in a type 2 diabetes mouse model of both DKD and DPN. Therefore, we compared the efficacy of a 12‐week regimen of three dietary interventions, low carbohydrate, caloric restriction, and alternate day fasting, for preventing complications in a db/db type 2 diabetes mouse model by performing metabolic, DKD, and DPN phenotyping. All three dietary interventions promoted weight loss, ameliorated glycemic status, and improved DKD, but did not impact percent fat mass and DPN. Multiple regression analysis identified a negative correlation between fat mass and motor nerve conduction velocity. Collectively, our data indicate that these three dietary interventions improved weight and glycemic status and alleviated DKD but not DPN. Moreover, diets that decrease fat mass may be a promising non‐pharmacological approach to improve DPN in type 2 diabetes given the negative correlation between fat mass and motor nerve conduction velocity.