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Abstract Efficient protein turnover is essential for cellular homeostasis and organ function. Loss of proteostasis is a hallmark of aging culminating in severe dysfunction of protein turnover. To investigate protein turnover dynamics as a function of age, we performed continuous in vivo metabolic stable isotope labeling in mice along the aging continuum. First, we discovered that the brain proteome uniquely undergoes dynamic turnover fluctuations during aging compared to heart and liver tissue. Second, trends in protein turnover in the brain proteome during aging showed sex-specific differences that were tightly tied to cellular compartments. Next, parallel analyses of the insoluble proteome revealed that several cellular compartments experience hampered turnover, in part due to misfolding. Finally, we found that age-associated fluctuations in proteasome activity were associated with the turnover of core proteolytic subunits, which was recapitulated by pharmacological suppression of proteasome activity. Taken together, our study provides a proteome-wide atlas of protein turnover across the aging continuum and reveals a link between the turnover of individual proteasome subunits and the age-associated decline in proteasome activity.

Abstract Background The accumulation of amyloid beta (Aβ) peptides in fibrils is prerequisite for Alzheimer’s disease (AD). Our understanding of the proteins that promote Aβ fibril formation and mediate neurotoxicity has been limited due to technical challenges in isolating pure amyloid fibrils from brain extracts. Methods To investigate how amyloid fibrils form and cause neurotoxicity in AD brain, we developed a robust biochemical strategy. We benchmarked the success of our purifications using electron microscopy, amyloid dyes, and a large panel of Aβ immunoassays. Tandem mass-spectrometry based proteomic analysis workflows provided quantitative measures of the amyloid fibril proteome. These methods allowed us to compare amyloid fibril composition from human AD brains, three amyloid mouse models, transgenic Aβ42 flies, and Aβ42 seeded cultured neurons. Results Amyloid fibrils are primarily composed by Aβ42 and unexpectedly harbor Aβ38 but generally lack Aβ40 peptides. Multidimensional quantitative proteomics allowed us to redefine the fibril proteome by identifying 20 new amyloid-associated proteins. Notably, we confirmed 57 previously reported plaque-associated proteins. We validated a panel of these proteins as bona fide amyloid-interacting proteins using antibodies and orthogonal proteomic analysis. One metal-binding chaperone metallothionein-3 is tightly associated with amyloid fibrils and modulates fibril formation in vitro. Lastly, we used a transgenic Aβ42 fly model to test if knock down or over-expression of fibril-interacting gene homologues modifies neurotoxicity. Here, we could functionally validate 20 genes as modifiers of Aβ42 toxicity in vivo. Conclusions These discoveries and subsequent confirmation indicate that fibril-associated proteins play a key role in amyloid formation and AD pathology.

Active pharmaceutical ingredients (API) with unfavorable physicochemical properties and stability present a significant challenge during their processing into final dosage forms. Cocrystallization of such APIs with suitable coformers is an efficient approach to mitigate the solubility and stability concerns. A considerable number of cocrystal-based products are currently being marketed and show an upward trend. However, to improve the API properties by cocrystallization, coformer selection plays a paramount role. Selection of suitable coformers not only improves the drug’s physicochemical properties but also improves the therapeutic effectiveness and reduces side effects. Numerous coformers have been used till date to prepare pharmaceutically acceptable cocrystals. The carboxylic acid-based coformers, such as fumaric acid, oxalic acid, succinic acid, and citric acid, are the most commonly used coformers in the currently marketed cocrystal-based products. Carboxylic acid-based coformers are capable of forming the hydrogen bond and contain smaller carbon chain with the APIs. This review summarizes the role of coformers in improving the physicochemical and pharmaceutical properties of APIs, and deeply explains the utility of afore-mentioned coformers in API cocrystal formation. The review concludes with a brief discussion on the patentability and regulatory issues related to pharmaceutical cocrystals.

Stability is an essential quality attribute of any pharmaceutical formulation. Poor stability can change the color and physical appearance of a drug, directly impacting the patient’s perception. Unstable drug products may also face loss of active pharmaceutical ingredients (APIs) and degradation, making the medicine ineffective and toxic. Moisture content is known to be the leading cause of the degradation of nearly 50% of medicinal products, leading to impurities in solid dose formulations. The polarity of the atoms in an API and the surface chemistry of API particles majorly influence the affinity towards water molecules. Moisture induces chemical reactions, including free water that has also been identified as an important factor in determining drug product stability. Among the various approaches, crystal engineering and specifically co-crystals, have a proven ability to increase the stability of moisture-sensitive APIs. Other approaches, such as changing the salt form, can lead to solubility issues, thus making the co-crystal approach more suited to enhancing hygroscopic stability. There are many reported studies where co-crystals have exhibited reduced hygroscopicity compared to pure API, thereby improving the product’s stability. In this review, the authors focus on recent updates and trends in these studies related to improving the hygroscopic stability of compounds, discuss the reasons behind the enhanced stability, and briefly discuss the screening of co-formers for moisture-sensitive drugs.

Cellulose derivatives have gained immense popularity as stabilizers for amorphous solid dispersion owing to their diverse physicochemical properties. More than 20 amorphous solid dispersion-based products that have been approved for marketing consist of cellulose derivatives as stabilizers, thus highlighting their importance in generation of amorphous solid dispersions. These polymers offer numerous advantages like drug solubilization, crystallization inhibition and improvement in release patterns of drugs. Exploring their potential and exploiting their chemistry and pH responsive behaviour have led to the synthesis of new derivatives that has broadened the scope of the use of cellulose derivatives in amorphous formulation development. The present review aims to provide an overview of different mechanisms by which these cellulose derivatives inhibit the crystallization of drugs in the solid state and from supersaturated solution. A summary of different categories of cellulose derivatives along with the newly explored polymers has been provided. A special segment on strengths, weaknesses, opportunities, and threats (SWOT) analysis and critical quality attributes (CQAs) which affect the performance of the cellulose based amorphous solid dispersion will aid the researchers in identifying the major challenges in the development of cellulose based solid dispersion and serve as a guide for further formulation development. Keywords: Supersaturation, HPMC, Amorphous form, Crystallization, Polymers

Deletions and mutations involving the Retinoic Acid Induced 1 (RAI1) gene at 17p11.2 cause Smith-Magenis syndrome (SMS). Here we report a patient with autism as the main clinical presentation, with some SMS-like features and a rare de novo RAI1 gene mutation, c.3440G > A (p.R1147Q). We functionally characterized the RAI1 p.R1147Q mutant protein. The mutation, located near the nuclear localization signal, had no effect on the subcellular localization of the mutant protein. However, similar to previously reported RAI1 missense mutations in SMS patients, the RAI1 p.R1147Q mutant protein showed a significant deficiency in activating in vivo transcription of a reporter gene driven by a BDNF (brain-derived neurotrophic factor) intronic enhancer. In addition, expression of other genes associated with neurobehavioral abnormalities and/or neurodevelopmental disorders were found to be altered in this patient. These results suggest a likely contribution of RAI1, either alone or in combination of other factors, to social behavior and reinforce the RAI1 gene as a candidate gene in patients with autistic manifestations or social behavioral abnormalities.

Background: Autism is characterized by difficulties in social interaction, communication, and repetitive behaviors; with different degrees of severity in each of the core areas. Haploinsufficiency and point mutations of RAI1 are associated with Smith-Magenis syndrome (SMS), a genetic condition that scores within the autism spectrum range for social responsiveness and communication, and is characterized by neurobehavioral abnormalities, intellectual disability, developmental delay, sleep disturbance, and self-injurious behaviors. Methods: To investigate the relationship between Rai1 and social impairment, we evaluated the Rai1+/− mice with a battery of tests to address social behavior in mice. Results: We found that the mutant mice showed diminished interest in social odors, abnormal submissive tendencies, and increased repetitive behaviors when compared to wild type littermates. Conclusions: These findings suggest that Rai1 contributes to social behavior in mice, and prompt it as a candidate gene for the social behaviors observed in Smith-Magenis Syndrome patients.

In this "Decade of Healthy Ageing," the integration of resilience into the healthy aging discourse becomes paramount, particularly in the context of indigenous communities grappling with the enduring effects of historical oppression, persistent poverty, and health disparities in their aging journey. Employing a phenomenological lens, this study seeks to derive the resilient characteristics exhibited by the Attappadi indigenous older adults of Kerala, aiming to explore the role of resilience in their pursuit of healthy aging. In-depth phenomenological interviews (n = 34), observation, and document analysis have revealed four key themes: A life course marked by adversities, Embracing the unyielding strength within, Personal resilience catalysts, and Extrinsic resilience catalysts. The participants exhibited a reasonably well-functioning collective, given their persistent adversities in their life course. Narratives illuminated a notable connection between the presence of resilience characteristics and the overall functioning of older adults. From a social work standpoint on resilience, this article underscores the vital interplay between individual agency and environmental factors in addressing adversity. The article advocates culturally sensitive, asset-based strategies to strengthen indigenous older adults' intrinsic and extrinsic resilience to ensure that they are not left behind in the global pursuit of healthy aging. [ABSTRACT FROM AUTHOR]

Phytoestrogen-rich diet alters the composition of gut microbiota by enhancing the growth of beneficial bacteria and decreasing the microbial load of pathogenic organisms. Drosophila is an invertebrate model system used for research studies, as it shares 70% genetic homology with humans. The present study aimed to analyse microbiological profile of phytoestrogen rich supplement and its impact on gutmicrobiome composition in Drosophila melanogaster. The phytoestrogen rich supplement was mixed with formula 424 plain and flies were exposed to it. Gut of flies was dissected and cell suspension was prepared. Bacterial colonies were developed by streaking method. Gram staining was performed to differentiate the bacterial cells and further gut microbiome composition (Acetobacteraceae and Lactobacillales taxa) was analysed by 16S rRNA sequencing. The microbiological analysis was carried out to ascertain the microbial load of the developed product for consumption. The total bacterial count and coliform counts of the phytoestrogen rich supplement were <10 CFU/g. Also, the developed supplement exhibited minimal yeast and mold growth (<1 CFU/g). Gram staining showed gram positive (Bacilli and cocci). 16S rRNA sequencing showed significance with mild variation in similarity. It confirmed the presence of Bacillus paramycoids. The developed supplement has showed improved gut microbiome composition in the Drosophila. In future, studies can be extended to humans to analyse the efficacy of the supplement in the gut microbiome composition. [ABSTRACT FROM AUTHOR]

The phenomenon of custodial grandparents has increased in South Asia and elsewhere, partly due to the growing trend of parents migrating for work, but often because of the untimely demise of one or both parents, illness, alcoholism and related issues affecting the birth parents. Adopting a phenomenological lens, this article explores the lived experiences and perceived needs of 10 custodial grandmothers from the Attappadi indigenous belt in Kerala to discuss how they cope with multiple challenges. Data gathering through indigenous storytelling methods and an interpretive phenomenological analysis points to new forms of feminisation of caregiving through custodial grandparenting, which require further research. Within the complex socio-economic and health contexts of the selected sample, our fieldwork explores the implications of the absence of the middle generation, which creates a network of intersecting disadvantages. We argue that the resulting calls for better support networks to assist these indigenous custodial grandmothers need to be addressed effectively at the levels of policy and practice. [ABSTRACT FROM AUTHOR]