Lipedema is an adipofascial disorder that almost exclusively affects women. Lipedema leads to chronic pain, swelling, and other discomforts due to the bilateral and asymmetrical expansion of subcutaneous adipose tissue. Although various distinctive morphological characteristics, such as the hyperproliferation of fat cells, fibrosis, and inflammation, have been characterized in the progression of lipedema, the mechanisms underlying these changes have not yet been fully investigated. In addition, it is challenging to reduce the excessive fat in lipedema patients using conventional weight-loss techniques, such as lifestyle (diet and exercise) changes, bariatric surgery, and pharmacological interventions. Therefore, lipedema patients also go through additional psychosocial distress in the absence of permanent treatment. Research to understand the pathology of lipedema is still in its infancy, but promising markers derived from exosome, cytokine, lipidomic, and metabolomic profiling studies suggest a condition distinct from obesity and lymphedema. Although genetics seems to be a substantial cause of lipedema, due to the small number of patients involved in such studies, the extrapolation of data at a broader scale is challenging. With the current lack of etiology-guided treatments for lipedema, the discovery of new promising biomarkers could provide potential solutions to combat this complex disease. This review aims to address the morphological phenotype of lipedema fat, as well as its unclear pathophysiology, with a primary emphasis on excessive interstitial fluid, extracellular matrix remodeling, and lymphatic and vasculature dysfunction. The potential mechanisms, genetic implications, and proposed biomarkers for lipedema are further discussed in detail. Finally, we mention the challenges related to lipedema and emphasize the prospects of technological interventions to benefit the lipedema community in the future.

Metabolic syndrome (MetS), characterized by obesity, insulin resistance, dyslipidemia, and hypertension, is a growing global health concern. This review examines the relationship between adipose tissue insulin resistance (AT-IR) and MetS. Adipose tissue functions beyond energy storage as an endocrine organ that regulates metabolism through hormone and cytokine secretion. When adipose tissue becomes insulin resistant, it contributes to systemic metabolic dysfunction through impaired glucose uptake and dysregulated adipokine production. This creates a bidirectional relationship where AT-IR promotes MetS development, while MetS-associated inflammation further worsens adipose insulin sensitivity. Key mechanisms include inflammatory signaling, altered adipokine profile, and mitochondrial dysfunction. Understanding these interactions offers therapeutic opportunities, as targeting adipose tissue function may provide novel approaches for MetS treatment. This review synthesizes current evidence on AT-IR-MetS interactions and discusses therapeutic implications and future research directions.

The concerning worldwide increase of obesity and chronic metabolic diseases, such as T2D, dyslipidemia, and cardiovascular disease, motivates further investigations into preventive and alternative therapeutic approaches. Over the past decade, there has been growing evidence that the formation and activation of thermogenic adipocytes (brown and beige) may serve as therapy to treat obesity and its associated diseases owing to its capacity to increase energy expenditure and to modulate circulating lipids and glucose levels. Thus, understanding the molecular mechanism of brown and beige adipocytes formation and activation will facilitate the development of strategies to combat metabolic disorders. Here, we provide a comprehensive overview of pathways and players involved in the development of brown and beige fat, as well as the role of thermogenic adipocytes in energy homeostasis and metabolism. Furthermore, we discuss the alterations in brown and beige adipose tissue function during obesity and explore the therapeutic potential of thermogenic activation to treat metabolic syndrome.

Obesity has reached epidemic proportions, driven by energy imbalance and limited capacity for adaptive thermogenesis. Brown (BAT) and beige adipose tissues dissipate energy through non-shivering thermogenesis (NST), primarily via uncoupling protein-1 (UCP1), making them attractive targets for increasing energy expenditure (EE). The canonical β-adrenergic pathway robustly activates NST in rodents through β3 adrenoceptors; however, translational success in humans has been limited by low β3 expression, off-target cardiovascular effects, and the emerging dominance of β2-mediated signaling in human BAT. Consequently, attention has shifted to non-adrenergic and UCP1-independent mechanisms that offer greater tissue distribution and improved safety profiles. This review examines a broad spectrum of alternative receptors and pathways—including GPRs, TRP channels, TGR5, GLP-1R, thyroid hormone receptors, estrogen receptors, growth hormone, BMPs, sirtuins, PPARs, and interleukin signaling—as well as futile substrate cycles (Ca²⁺, creatine, and glycerol-3-phosphate) that sustain thermogenesis in beige adipocytes and skeletal muscle. Pharmacological agents (natural compounds, peptides, and small molecules) and non-pharmacological interventions (cold exposure, exercise, diet, and time shift) targeting these pathways are critically evaluated. We highlight the translational gaps between rodent and human studies, the promise of multimodal therapies combining low-dose adrenergic agents with non-adrenergic activators, and emerging strategies such as sarco/endoplasmic reticulum calcium ATPase protein (SERCA) modulators and tissue-specific delivery. Ultimately, integrating adrenergic and non-adrenergic approaches holds the greatest potential for safe, effective, and sustainable obesity management.

Cytoplasmic dynein heavy chain (DYNC1H1) is a multi-subunit protein complex that provides motor force for movement of cargo on microtubules and traffics them back to the soma. In humans, mutations along the DYNC1H1 gene result in intellectual disabilities, cognitive delays, and neurologic and motor deficits. The aim of the study was to generate a mouse model to a newly identified de novo heterozygous DYNC1H1 mutation, within a functional ATPase domain (c9052C > T(P3018S)), identified in a child with motor deficits, and intellectual disabilities. P3018S heterozygous (HET) knockin mice are viable; homozygotes are lethal. Metabolic and EchoMRI™ testing show that HET mice have a higher metabolic rate, are more active, and have less body fat compared to wildtype mice. Neurobehavioral studies show that HET mice perform worse when traversing elevated balance beams, and on the negative geotaxis test. Immunofluorescent staining shows neuronal migration abnormalities in the dorsal and lateral neocortex with heterotopia in layer I. Neuron-subtype specific transcription factors CUX1 and CTGF identified neurons from layers II/III and VI respectively in cortical layer I, and abnormal pyramidal neurons with MAP2+ dendrites projecting downward from the pial surface. The HET mice are a good model for the motor deficits seen in the child, and highlights the importance of cytoplasmic dynein in the maintenance of cortical function and dendritic orientation relative to the pial surface. Our results are discussed in the context of other dynein mutant mice and in relation to clinical presentation in humans with DYNC1H1 mutations.

Background/Objectives: Children and teenagers display a distinct metabolic dysfunction-associated steatohepatitis (MASH) phenotype, yet studies of childhood MASH are scarce and validated animal models lacking, limiting the development of treatments. Poor vitamin C (VitC) status may affect MASH progression and often co-occurs with high-fat diets and related metabolic imbalances. As a regulator of DNA methylation, poor VitC status may further contribute to MASH by regulating gene expression This study investigated guinea pigs—a species that, like humans, depends on vitC in the diet—as a model of pediatric MASH, examining the effects of poor VitC status on MASH hallmarks and global DNA methylation levels. Methods: Sixty-two juvenile guinea pigs were exposed to a high-fat diet for 16 weeks. Results: Juvenile guinea pigs exhibited hepatic histopathology representative of pediatric MASH, confirmed by portal inflammation and fibrosis. Consistent with pediatric MASH, juvenile guinea pigs displayed increased lobular and portal inflammation (p < 0.05 and p < 0.0001, respectively) but less steatosis (p < 0.001) compared to adults. Compared to the controls, the guinea pigs deprived in VitC showed lower body weight (p < 0.01), higher expression of hepatic inflammatory genes (p < 0.05), and a lower global hydroxymethylcytosine to methylcytosine ratio in the high-fat groups (p < 0.05). Conclusions: Our study validates guinea pigs as a model of pediatric MASH and suggests that VitC contributes to an altered gene expression signature through the regulation of DNA hydroxymethylation. We postulate that nutritional co-deficiencies in MASH, such as low VitC, may accelerate disease progression and deserve further attention.