Transcription factor EB (TFEB) is considered the master transcriptional regulator of autophagy and lysosomal biogenesis, which regulates target gene expression through binding to CLEAR motifs. TFEB dysregulation has been linked to the development of numerous pathological conditions; however, several other lines of evidence show that TFEB might be a point of convergence of diverse signaling pathways and might therefore modulate other important biological processes such as cellular senescence, DNA repair, ER stress, carbohydrates, and lipid metabolism and WNT signaling-related processes. The regulation of TFEB occurs predominantly at the post-translational level, including phosphorylation, acetylation, SUMOylating, PARsylation, and glycosylation. It is noteworthy that TFEB activation is context-dependent; therefore, its regulation is subjected to coordinated mechanisms that respond not only to nutrient fluctuations but also to stress cell programs to ensure proper cell homeostasis and organismal health. In this review, we provide updated insights into novel post-translational modifications that regulate TFEB activity and give an overview of TFEB beyond its widely known role in autophagy and the lysosomal pathway, thus opening the possibility of considering TFEB as a potential therapeutic target.

Giardiasis remains a significant global health issue, and its treatment is increasingly hampered by the emergence of drug resistance and cross-resistance between nitroimidazoles and nitazoxanide. In this study, we evaluated the in vitro antigiardial activity, cytotoxicity, and potential mechanisms of action of seven structural analogs (CLB 1–7) derived from a hybrid structure combining nitazoxanide and clofibric acid. Among them, compounds CLB-3 and CLB-5 emerged as the most potent candidates, demonstrating exceptional efficacy against a nitazoxanide-resistant (NTZr) strain of Giardia lamblia, with potencies up to 43 and 60 times higher than that of the reference drug, respectively. Furthermore, both compounds demonstrated high selectivity for the parasite, exhibiting low cytotoxicity in human Caco-2 cells. To investigate the mechanism of action, functional biochemical assays revealed that treatment with these derivatives significantly reduced the intracellular ATP levels and altered the ADP/ATP ratio, indicating a direct impact on the parasite’s energy metabolism. These functional findings correlate closely with RT-qPCR transcriptional analyses and in silico molecular dynamics simulations; collectively, the data suggest a multi-target mechanism of action that may involve the disruption of energy homeostasis and the possible inhibition of key enzymes in the glycolytic pathway (PFOR, G6PD::6PGL, PK, and PPDK). In summary, these results identify compounds CLB-3 and CLB-5 as highly promising chemotherapeutic candidates for combating refractory giardiasis.

Autophagy is a cellular catabolic mechanism that facilitates the degradation of cytoplasmic components, thereby restoring energy homeostasis and mitigating cellular damage. This process functions as a housekeeping system, essential for maintaining organismal viability under stressful conditions. Numerous studies have highlighted the role of autophagy in regulating various physiological processes, including metabolic pathways. Notably, certain autophagy-related genes may play a relevant role in metabolic disorders, extending beyond their involvement in the autophagic process, and may offer potential therapeutic avenues for treating energy-related metabolic diseases. This review summarizes the roles of various components of each autophagic complex and the regulators involved in the autophagic process. In particular, it explores the intricate relationship between autophagy and several metabolic diseases, including type 2 diabetes mellitus (T2DM), obesity, and non-alcoholic fatty liver disease (NAFLD).