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Introduction: Obesity, one of the most frequent health problems in the adult population, is a condition characterized by excessive white adipose tissue accumulation and accompanied by the increased risk to develop other disorders such as type II diabetes, cardiovascular disorders, physical disability, frailty and sarcopenia. Total fat mass frequently increases during aging, often coexisting with sarcopenia, thus resulting in an emerging condition defined sarcopenic obesity (SO). Our previous data demonstrated the relevant role of the bromo and extra-terminal domain (BET) proteins inhibitor JQ1 in attenuating inflammation and fibrosis in sarcopenic mice. Moreover, we preliminarily observed that JQ1 administration markedly reduces white adipose tissue mass, suggesting a potential role of BET proteins on visceral fat deposition during aging. Objectives: Starting from those observations, the aim of this study was to investigate the ability of JQ1 to reduce adiposity in a chronic diet-induced obesity (DIO) mouse model mimicking the human metabolic syndrome. Methods: Male C57BL/6J mice were divided in subgroups, either fed a standard diet or a high fat diet for 22 or 12 weeks, treated over the last 14 days with JQ1 or with vehicle. Results: The results showed that JQ1 administration reduces fat mass, preserving skeletal muscle mass and function. A direct JQ1 lipolytic effect was demonstrated on mature adipocyte cultures. JQ1-mediated loss of adipose tissue mass was not associated with systemic inflammation or with lipid accumulation in muscle and liver. JQ1 administration did not impinge on skeletal muscle metabolism and oxidative capability, as shown by the lack of significant impact on mitochondrial mass and biogenesis. Conclusion: In conclusion, the current data highlight a potential benefit of JQ1 administration to counteract obesity, suggesting epigenetic modulation as a prospective target in the treatment of obesity and sarcopenic obesity, despite the underlying multiorgan molecular mechanism is still not completely elucidated.

Proteostasis, the maintenance of cellular protein balance, is essential for cell viability and is highly conserved across all organisms. Newly synthesized proteins, or "clients," undergo sequential processing by Hsp40, Hsp70, and Hsp90 chaperones to achieve proper folding and functionality. Despite extensive characterization of post-translational modifications (PTMs) on Hsp70 and Hsp90, the modifications on Hsp40 remain less understood. This study aims to elucidate the role of lysine acetylation on the yeast Hsp40, Ydj1. By mutating acetylation sites on Ydj1's J-domain to either abolish or mimic constitutive acetylation, we observed that preventing acetylation had no noticeable phenotypic impact, whereas acetyl-mimic mutants exhibited various defects indicative of impaired Ydj1 function. Proteomic analysis revealed several Ydj1 interactions affected by J-domain acetylation, notably with proteins involved in translation. Further investigation uncovered a novel role for Ydj1 acetylation in stabilizing ribosomal subunits and ensuring translational fidelity. Our data suggest that acetylation may facilitate the transfer of Ydj1 between Ssa1 and Hsp82. Collectively, this work highlights the critical role of Ydj1 acetylation in proteostasis and translational fidelity.

In the present work, more than one hundred and thirty lithic artefacts rediscovered in several archaeological sites dating from the Upper Palaeolithic to the Middle Ages from Calabria (Southern Italy) were petroarchaeometrically characterised through minimally invasive techniques. In more detail, 110 specimens were found in the Grotta della Monaca site (Sant’Agata di Esaro), and the other 23 belong to a collection kept in the Museo Nazionale Preistorico ed Etnografico “Luigi Pigorini” (Roma), coming from several localities (Longobucco, Spezzano della Sila, Cicala, Gimigliano, Roccaforte del Greco, and Bova). For preservation needs, 2 small axes in polished stone and 2 obsidians collected from Grotta della Monaca were analysed by absolutely non-destructive techniques. Optical and electron microscopic investigations, sometimes integrated with wavelength-dispersive X-ray fluorescence spectroscopy and X-ray diffraction spectrometry, allowed us to ascertain that the source area of all the lithic tools was in Calabria, except for obsidians, which come from the island of Lipari (Messina, Southern Italy). For a small number of particularly favourable cases, it was possible to define with great precision the outcrop area of the used rocks given their textural and mineralogical features. The specific source area contained a pickaxe originating from Cetraro–Fuscaldo metabasalt (lawsonite–albite facies) outcrops and two small axes in polished stone, one derived from migmatitic metapelites from Palmi and the other from meta-ultramafic rocks from Curinga. The choice of the used lithologies, harder or softer, had to be linked to the use that humans had to make of the lithic artefacts.

Voltage-gated sodium channel NaV1.8 regulates transmission of pain signals to the brain. While NaV1.8 has the potential to serve as a drug target, the molecular mechanisms that shape NaV1.8 gating are not completely understood, particularly mechanisms that couple activation to inactivation. Interactions between toxin producing animals and their predators provide a novel approach for investigating NaV structure-function relationships. Arizona bark scorpions produce Na+ channel toxins that initiate pain signaling. However, in predatory grasshopper mice, toxins inhibit NaV1.8 currents and block pain signals. A screen of synthetic peptide toxins predicted from bark scorpion venom showed that peptide NaTx36 inhibited Na+ current recorded from a recombinant grasshopper mouse NaV1.8 channel (OtNaV1.8). Toxin NaTx36 hyperpolarized OtNaV1.8 activation, steady-state fast inactivation, and slow inactivation. Mutagenesis revealed that the first gating charge in the domain I (DI) S4 voltage sensor and an acidic amino acid (E) in the DII SS2 - S6 pore loop are critical for the inhibitory effects of NaTx36. Computational modeling showed that a DI S1 - S2 asparagine (N) stabilizes the NaTx36 - OtNaV1.8 complex while residues in the DI S3 - S4 linker and S4 voltage sensor form electrostatic interactions that allow a toxin glutamine (Q) to contact the first S4 gating charge. Surprisingly, the models predicted that NaTx36 contacts amino acids in the DII S5 - SS1 pore loop instead of the SS2 - S6 loop; the DII SS2 - S6 loop motif (QVSE) alters the conformation of the DII S5 - SS1 pore loop, enhancing allosteric interactions between toxin and the DII S5 - SS1 pore loop. Few toxins have been identified that modify NaV1.8 gating. Moreover, few toxins have been described that modify sodium channel gating via the DI S4 voltage sensor. Thus, NaTx36 and OtNaV1.8 provide tools for investigating the structure-activity relationship between channel activation and inactivation gating, and the connection to alternative pain phenotypes.

Angiosarcoma is a rare and aggressive neoplasia of endothelial cells which represents only 2% of all soft-tissue tumors and frequently occurs in the skin and subcutaneous tissues. It is classified in two groups: the first is represented by primary angiosarcoma, which includes cutaneous and breast angiosarcoma; the second is constituted by secondary angiosarcoma, which is related to radiation therapy, lymphedema, exposure to some chemical toxins, and familiar syndromes. Post-radiation intestinal angiosarcoma is a special type of secondary angiosarcoma, and only a few cases have been reported in the literature. We present a case of radiation-induced small bowel angiosarcoma in an 88-year-old female patient who was admitted to our department for abdominal pain and signs of intestinal obstruction. Her clinical history included previous radiotherapy treatments after a hysterectomy for uterine fibroids, excision of the vaginal stump for squamous cell carcinoma, and the surgical removal of a left-leg cutaneous angiosarcoma. She underwent emergency surgery, and features of peritoneal carcinomatosis were detected. A histological examination showed the presence of a small intestinal angiosarcoma. At the histochemical analysis, MYC amplification was detected, suggesting that her small bowel angiosarcoma was related to past radiation treatments.

The Consortium for Top-Down Proteomics (www.topdownproteomics.org) launched the present study to assess the current state of top-down mass spectrometry (TD MS) and middle-down mass spectrometry (MD MS) for characterizing monoclonal antibody (mAb) primary structures, including their modifications. To meet the needs of the rapidly growing therapeutic antibody market, it is important to develop analytical strategies to characterize the heterogeneity of a therapeutic product's primary structure accurately and reproducibly. The major objective of the present study is to determine whether current TD/MD MS technologies and protocols can add value to the more commonly employed bottom-up (BU) approaches with regard to confirming protein integrity, sequencing variable domains, avoiding artifacts, and revealing modifications and their locations. We also aim to gather information on the common TD/MD MS methods and practices in the field. A panel of three mAbs was selected and centrally provided to 20 laboratories worldwide for the analysis: Sigma mAb standard (SiLuLite), NIST mAb standard, and the therapeutic mAb Herceptin (trastuzumab). Various MS instrument platforms and ion dissociation techniques were employed. The present study confirms that TD/MD MS tools are available in laboratories worldwide and provide complementary information to the BU approach that can be crucial for comprehensive mAb characterization. The current limitations, as well as possible solutions to overcome them, are also outlined. A primary limitation revealed by the results of the present study is that the expert knowledge in both experiment and data analysis is indispensable to practice TD/MD MS.

Malignant gastrointestinal neuroectodermal tumor (GNET) is an infrequent soft-tissue sarcoma, formerly referred to as clear-cell sarcoma-like gastrointestinal tumor (CCSLGT) and frequently reported in the literature as clear-cell sarcoma of the gastrointestinal tract (CCS-GI); it is characterized by an absence of melanocytic differentiation and the presence of nontumoral osteoclast-like giant cells (OLGCs). The current study reports a case of a 79 year old woman admitted to the emergency department (ED) with symptoms of constipation and intestinal obstruction; a mass was found within the ileal wall necessitating of surgical approach. Immunohistochemically, tumor cells surprisingly had the hallmark of GNETs. Unfamiliarity with tumors with the features of GNETs can easily lead to a misdiagnosis by surgical pathologist. Therefore, comprehensive evaluation, including morphology and additional studies, is required for an appropriated diagnosis. Furthermore, without a high index of suspicion, there is actually no consensus on staging or treatment.

A 70-year-old man was admitted to the Emergency Department (ED) for marked asthenia and severe anemia. In addition, a high level of lipase was found. During hospitalization, a locally advanced gastric cancer was diagnosed, with endoscopic evidence of a large polyploid formation originating under the cardias that occupied most of the gastric lumen. A total body CT scan was performed before surgery; the tumor affected the posterior gastric wall, with tenacious infiltration of the pancreatic body. Therefore, we performed a total gastrectomy with esophageal jejunum anastomosis and reconstruction of intestinal continuity according to Roux, distal spleno-pancreatectomy, and cholecystectomy. At histology, a pancreatic acinar cell carcinoma (PACC) with full thickness infiltration of the gastric wall was diagnosed. Acinar cell carcinomas are highly aggressive neoplasms, and surgical resection, when feasible, is the treatment of choice regardless of size, also because the role of neoadjuvant or adjuvant chemo- or radiotherapy remains uncodified.

One gene can give rise to many functionally distinct proteoforms, each of which has a characteristic molecular mass. Top-down mass spectrometry enables the analysis of intact proteins and proteoforms. Here members of the Consortium for Top-Down Proteomics provide a decision tree that guides researchers to robust protocols for mass analysis of intact proteins (antibodies, membrane proteins and others) from mixtures of varying complexity. We also present cross-platform analytical benchmarks using a protein standard sample, to allow users to gauge their proficiency.

[Display omitted] • BRD4 pharmacologic inhibition triggers rapid body weight loss. • JQ1 induces adipose tissue depletion preserving skeletal muscle mass and strength. • JQ1-induced adipose tissue loss does not alter systemic glucose and improves lipid homeostasis. • JQ1 exerts a lipolytic action, inducing ATGL and HSL transcripts in the adipose tissue. • In vitro, JQ1 reduces lipid accumulation and increases glycerol release in mature adipocytes. Obesity, one of the most frequent health problems in the adult population, is a condition characterized by excessive white adipose tissue accumulation and accompanied by the increased risk to develop other disorders such as type II diabetes, cardiovascular disorders, physical disability, frailty and sarcopenia. Total fat mass frequently increases during aging, often coexisting with sarcopenia, thus resulting in an emerging condition defined sarcopenic obesity (SO). Our previous data demonstrated the relevant role of the bromo and extra-terminal domain (BET) proteins inhibitor JQ1 in attenuating inflammation and fibrosis in sarcopenic mice. Moreover, we preliminarily observed that JQ1 administration markedly reduces white adipose tissue mass, suggesting a potential role of BET proteins on visceral fat deposition during aging. Starting from those observations, the aim of this study was to investigate the ability of JQ1 to reduce adiposity in a chronic diet-induced obesity (DIO) mouse model mimicking the human metabolic syndrome. Male C57BL/6J mice were divided in subgroups, either fed a standard diet or a high fat diet for 22 or 12 weeks, treated over the last 14 days with JQ1 or with vehicle. The results showed that JQ1 administration reduces fat mass, preserving skeletal muscle mass and function. A direct JQ1 lipolytic effect was demonstrated on mature adipocyte cultures. JQ1-mediated loss of adipose tissue mass was not associated with systemic inflammation or with lipid accumulation in muscle and liver. JQ1 administration did not impinge on skeletal muscle metabolism and oxidative capability, as shown by the lack of significant impact on mitochondrial mass and biogenesis. In conclusion, the current data highlight a potential benefit of JQ1 administration to counteract obesity, suggesting epigenetic modulation as a prospective target in the treatment of obesity and sarcopenic obesity, despite the underlying multiorgan molecular mechanism is still not completely elucidated. [ABSTRACT FROM AUTHOR]

Simple Summary: Cancer patients frequently develop a syndrome named cachexia that causes severe muscle loss and frailty, eventually representing the cause of death. Muscle atrophy and muscle weakness are characterized by massive degradation of endogenous proteins, potentially consequent to excessive disposal of mitochondria through the selective autophagic process of mitophagy. This study explored whether selectively silencing BNIP3, a mitophagy-related protein upregulated in the muscle of both mouse and human cancer hosts, could help in preventing muscle loss. Two distinct methodological silencing approaches were tested, either by electroporation of a plasmid or via adenoviral particle injection. Although the first method was ineffective in tumor-bearing mice, the adenovirus-based approach significantly reduced BNIP3 levels and moderately increased muscle fiber size, suggesting partial prevention of muscle atrophy. BNIP3 silencing also maintained mitochondrial mass without disrupting oxidative balance, highlighting BNIP3's central role in cancer cachexia and suggesting that targeting BNIP3 may help in supporting muscle health in cancer patients. Background and Aims: Cancer cachexia is a complex syndrome affecting most cancer patients and is directly responsible for about 20% of cancer-related deaths. Previous studies showed muscle proteolysis hyper-activation and mitophagy induction in tumor-bearing animals. While basal mitophagy is required for maintaining muscle mass and quality, excessive mitophagy promotes uncontrolled protein degradation, muscle loss and impaired function. BNIP3, a key mitophagy-related protein, is significantly increased in the muscles of both mice and human cancer hosts. This study aimed to define the potential of mitigating mitophagy via BNIP3 downregulation in preserving mitochondrial integrity, counteracting skeletal muscle loss in experimental cancer cachexia. Methods: Two in vivo gene delivery methods were performed to knock down muscle BNIP3: electroporation of a BNIP3-specific shRNA expression vector or adenovirus injection. Results: The electroporation effectively reduced muscle BNIP3 in healthy mice but was ineffective in C26 tumor-bearing mice. In contrast, adenovirus-mediated BNIP3 knockdown successfully decreased BNIP3 levels also in tumor hosts. Although BNIP3 knockdown did not impact overall on body or muscle mass, it improved muscle fiber size in C26-bearing miceh2, suggesting partial prevention of muscle atrophy. Mitochondrial respiratory chain complexes (OxPhos) and TOM20 protein levels were consistently rescued, indicating improvements in mitochondrial mass, while H2O2 levels were unchanged among the groups, suggesting that BNIP3 downregulation does not impair the endogenous control of oxidative balance. Conclusions: These findings suggest that a fine balance between mitochondrial disposal and biogenesis is fundamental for preserving muscle homeostasis and highlight a potential role for BNIP3 modulation against cancer-induced muscle wasting. [ABSTRACT FROM AUTHOR]

Proteostasis, the maintenance of cellular protein balance, is essential for cell viability and is highly conserved across all organisms. Newly synthesized proteins, or "clients," undergo sequential processing by Hsp40, Hsp70, and Hsp90 chaperones to achieve proper folding and functionality. Despite extensive characterization of post-translational modifications (PTMs) on Hsp70 and Hsp90, the modifications on Hsp40 remain less understood. This study aims to elucidate the role of lysine acetylation on the yeast Hsp40, Ydj1. By mutating acetylation sites on Ydj1's J-domain to either abolish or mimic constitutive acetylation, we observed that preventing acetylation had no noticeable phenotypic impact, whereas acetyl-mimic mutants exhibited various defects indicative of impaired Ydj1 function. Proteomic analysis revealed several Ydj1 interactions affected by J-domain acetylation, notably with proteins involved in translation. Further investigation uncovered a novel role for Ydj1 acetylation in stabilizing ribosomal subunits and ensuring translational fidelity. Our data suggest that acetylation may facilitate the transfer of Ydj1 between Ssa1 and Hsp82. Collectively, this work highlights the critical role of Ydj1 acetylation in proteostasis and translational fidelity. Author summary: Cells require a suite of chaperone and co-chaperone proteins to maintain a healthy balance of functional proteins. A large number of modifications on chaperone and co-chaperone proteins have been identified, but their functional importance has not been fully explored. In this study, we identify acetylation sites on the yeast co-chaperone Ydj1 that impact its interactions with major chaperones and client proteins including those involved in protein synthesis. This work sheds light on how modifications on co-chaperones can also play an important role in the health of the proteome. [ABSTRACT FROM AUTHOR]

Analysis of whole proteins by mass spectrometry, or top-down proteomics, has several advantages over methods relying on proteolysis. For example, proteoforms can be unambiguously identified and examined. However, from a gas-phase ion-chemistry perspective, proteins are enormous molecules that present novel challenges relative to peptide analysis. Herein, the statistics of cleaving the peptide backbone multiple times are examined to evaluate the inherent propensity for generating internal versus terminal ions. The raw statistics reveal an inherent bias favoring production of terminal ions, which holds true regardless of protein size. Importantly, even if the full suite of internal ions is generated by statistical dissociation, terminal ions are predicted to account for at least 50% of the total ion current, regardless of protein size, if there are three backbone dissociations or fewer. Top-down analysis should therefore be a viable approach for examining proteins of significant size. Comparison of the purely statistical analysis with actual top-down data derived from ultraviolet photodissociation (UVPD) and higher-energy collisional dissociation (HCD) reveals that terminal ions account for much of the total ion current in both experiments. Terminal ion production is more favored in UVPD relative to HCD, which is likely due to differences in the mechanisms controlling fragmentation. Importantly, internal ions are not found to dominate from either the theoretical or experimental point of view. Graphical abstract ᅟ.

Hsp70 interactions are critical for cellular viability and the response to stress. Previous attempts to characterize Hsp70 interactions have been limited by their transient nature and the inability of current technologies to distinguish direct versus bridged interactions. We report the novel use of cross-linking mass spectrometry (XL-MS) to comprehensively characterize the Saccharomyces cerevisiae (budding yeast) Hsp70 protein interactome. Using this approach, we have gained fundamental new insights into Hsp70 function, including definitive evidence of Hsp70 self-association as well as multipoint interaction with its client proteins. In addition to identifying a novel set of direct Hsp70 interactors that can be used to probe chaperone function in cells, we have also identified a suite of posttranslational modification (PTM)-associated Hsp70 interactions. The majority of these PTMs have not been previously reported and appear to be critical in the regulation of client protein function. These data indicate that one of the mechanisms by which PTMs contribute to protein function is by facilitating interaction with chaperones. Taken together, we propose that XL-MS analysis of chaperone complexes may be used as a unique way to identify biologically important PTMs on client proteins.

Peritoneal carcinomatosis (PC) is defined as a metastatic involvement of the peritoneum by several other primary sites and it is characterized by a marked worsening of prognosis, with limited treatment opportunities. Subsequently, PC should be ruled out before any invasive treatment is administered. A new through-the-needle micro-biopsy forceps (MF) was recently introduced that permits micro-histology cores. In this case series, we evaluated the feasibility of MF in the assessment of PC to complete patient diagnostic work-ups. Five consecutive patients referred for endoscopic ultrasound staging were sampled using MF. Sampling was feasible in all patients with a technical success of 100%. No adverse events were reported in any cases. This technique was feasible and safe with a technical success rate of 100%. It permitted sampling of peritoneal irregularity, obtained high-quality tissue fragments in all cases, and enabled an additional assessment, i.e., immunohistochemical staining.

A new occurrence of the Mn-Ba ore mineral, romanechite, has been discovered in a small paleo-doline of the Apulian karst on Mesozoic carbonate rock successions, characterized by reddish incrustations and nodules made essentially by Fe-bearing calcite. The conditions under which Mn-Ba ore minerals form represent an intriguing area of research, as these minerals can act as scavengers for heavy elements, impacting soils, surface sediments, and even associated aquatic systems. The genesis of romanechite is linked to the progressive interaction of silicate aqueous solutions enriched in Al, Si, and Fe with the limestone substrate. The findings provide new insights into the genetic processes responsible for the formation of reddish Mn incrustations, supporting their polygenetic origin because of the chemical alteration of limestone and allochthonous siliciclastic muds. [ABSTRACT FROM AUTHOR]

STUDY QUESTION Is IVF indicated for couples with age-related infertility? SUMMARY ANSWER IVF may be of doubtful utility for age-related infertility. WHAT IS KNOWN ALREADY A diagnosis of unexplained infertility is drawn when the diagnostic work-up fails to identify any patent cause. Although typically managed uniformly, unexplained infertility is likely to comprise a wide range of conditions, including age-related infertility (at least in older women). Unfortunately, no validated tests for the identification of age-related infertility exist and these women are typically treated as unexplained cases. However, homologous ART may be less effective for these women because these techniques may be unable to treat the detrimental effects of ageing on oocyte competence. STUDY DESIGN, SIZE, DURATION Women aged 18–42 years who underwent IVF procedures between January 2014 and December 2021 were selected retrospectively. In the first part of the study, we aimed to assess whether the proportion of women with unexplained infertility (i.e. without patent causes of infertility) increased with age. In the second part of the study, women with unexplained infertility were matched 1:1 by age, study period, and duration of infertility, to those with a patent cause of infertility. If our hypothesis is valid, the first part of the study should highlight an increase in the proportion of unexplained infertility with age. Moreover, in the second part of the study, one should observe a sharper decrease in the rate of IVF success of the procedure with age in women with an unremarkable work-up compared to those with a definite cause of infertility. PARTICIPANTS/MATERIALS, SETTING, METHODS Women were included if: they had been trying to conceive for more than 2 years, they had retrieved more than three oocytes, and had not undergone previous IVF attempts. We exclude couples with severe male factor (criptozoospermia), chronic anovulation, untreated hydrosalpinx, or intracavitary diseases. The first part of the study aimed at investigating the relative proportion of unexplained infertility with age. The outcome of the second part was the distribution of the live births between unexplained versus explained infertility, in women younger or older than 35 years. Only the results of the first IVF cycle were considered (including both fresh and frozen cycles). The live birth rate corresponded to the cumulative chance of a live birth per oocyte retrieval. MAIN RESULTS AND THE ROLE OF CHANCE One thousand five hundred and thirty-five women were selected for the first part of the study; 742 of them had unexplained infertility (48%). The frequency of this diagnosis was lower among women aged <35 years (40%) compared to those ≥35 years (52%) (P  < 0.001). A clear gradient emerged when considering smaller intervals of age (P  < 0.001). A total of 1134 women (567 unexplained cases and 567 explained cases) were selected for the second part of the study. Baseline variables were comparable between women with unexplained and explained infertility. Among women younger than 35 years (n = 229 unexplained cases and 229 explained cases), 108 live births were observed in women with unexplained infertility (47%) and 88 in those with explained infertility (38%). In comparison, among women older than 35 years, the live births occurred in 90 (27%) and 114 (34%) couples, respectively (P  = 0.03). The adjusted odds ratio (OR) for a live birth in older women with unexplained infertility was 0.63 (95% CI: 0.43–0.94). In other words, the effectiveness of IVF in older women with unexplained infertility is reduced by an additional 37% when compared to women of similar age with a patent cause of infertility. Moreover, when considering smaller intervals of age, a gradient of the adverse effect of age on the distribution of live births between unexplained and explained infertility emerged (P  = 0.003). Overall, these results support the hypothesis that IVF may be of modest benefit in women with age-related infertility. The decline in IVF success is sharper in women with unexplained infertility compared to those with explained infertility, indirectly suggesting that IVF cannot effectively treat age-related infertility. LIMITATIONS, REASONS FOR CAUTION We postulated that the greater decline in IVF success with age in the unexplained group could be related to the concomitant increase in the proportion of women with age-related infertility. However, even if this is theoretically logical, the unavailability of validated tools to diagnose age-related infertility makes our inference speculative. We cannot exclude that the prevalence of other unknown causes of infertility that cannot also be effectively overcome with IVF could increase with age. WIDER IMPLICATIONS OF THE FINDINGS Our findings suggest that IVF may be of modest utility for treating age-related infertility. Offering this procedure to older women with an unremarkable infertility work-up may be questioned. However, the diagnosis of age-related infertility remains challenging and identifying a biomarker that could reliably diagnose age-related infertility is a priority. STUDY FUNDING/COMPETING INTEREST(S) The study was partially funded by the Italian Ministry of Health—current research IRCCS and by a specific grant supported by Ferring. ES declares receiving honoraria for lectures at meetings from IBSA and Gedeon-Richter and he also handles private grants of research from Ferring, IBSA, Theramex, and Gedeon-Richter. All the other authors do not have any conflict of interest to declare. TRIAL REGISTRATION NUMBER N/A. [ABSTRACT FROM AUTHOR]

Voltage-gated sodium channel NaV1.8 regulates transmission of pain signals to the brain. While NaV1.8 has the potential to serve as a drug target, the molecular mechanisms that shape NaV1.8 gating are not completely understood, particularly mechanisms that couple activation to inactivation. Interactions between toxin producing animals and their predators provide a novel approach for investigating NaV structure-function relationships. Arizona bark scorpions produce Na+ channel toxins that initiate pain signaling. However, in predatory grasshopper mice, toxins inhibit NaV1.8 currents and block pain signals. A screen of synthetic peptide toxins predicted from bark scorpion venom showed that peptide NaTx36 inhibited Na+ current recorded from a recombinant grasshopper mouse NaV1.8 channel (OtNaV1.8). Toxin NaTx36 hyperpolarized OtNaV1.8 activation, steady-state fast inactivation, and slow inactivation. Mutagenesis revealed that the first gating charge in the domain I (DI) S4 voltage sensor and an acidic amino acid (E) in the DII SS2 – S6 pore loop are critical for the inhibitory effects of NaTx36. Computational modeling showed that a DI S1 – S2 asparagine (N) stabilizes the NaTx36 – OtNaV1.8 complex while residues in the DI S3 – S4 linker and S4 voltage sensor form electrostatic interactions that allow a toxin glutamine (Q) to contact the first S4 gating charge. Surprisingly, the models predicted that NaTx36 contacts amino acids in the DII S5 – SS1 pore loop instead of the SS2 – S6 loop; the DII SS2 – S6 loop motif (QVSE) alters the conformation of the DII S5 – SS1 pore loop, enhancing allosteric interactions between toxin and the DII S5 – SS1 pore loop. Few toxins have been identified that modify NaV1.8 gating. Moreover, few toxins have been described that modify sodium channel gating via the DI S4 voltage sensor. Thus, NaTx36 and OtNaV1.8 provide tools for investigating the structure-activity relationship between channel activation and inactivation gating, and the connection to alternative pain phenotypes.

Monoclonal antibodies (mAbs) are protein biotherapeutics with a proven efficacy toward fighting life-threatening diseases. Their exceptional healing potential drives the annual increase in the number of novel mAbs and other antibody-like molecules entering clinical trials and the number of approved mAb-based drugs. Mass spectrometry (MS) offers high selectivity and specificity for the potentially unambiguous identification and comprehensive structural characterization of proteins, including at the proteoform level. It is thus not surprising that MS-based approaches are playing a central role in the biopharma laboratories, complementing and advancing traditional biotherapeutics characterization workflows. A combination of MS approaches is required to comprehensively characterize mAbs’ structures: the commonly employed bottom-up MS approaches are efficiently complemented with mass measurements at the intact and subunit (middle-up) levels, together with product ion analysis following gas-phase fragmentation of precursor ions performed at the intact (top-down) and subunit (middle-down) levels. Here we overview our group’s contribution to increasing the efficiency of these approaches and the development of the novel strategies over the past decade. Our particular focus has been on the top-down and middle-down MS methods that utilize electron transfer dissociation (ETD) for gas-phase protein ion fragmentation. Several approaches pioneered by our group, particularly an ETD-based middle-down approach, constitute a part of commercial software solutions for the mAb’s characterization workflows.

With the implementation of COVID-19 vaccine up-take, doubts regarding the impact of immunization on future fertility have begun to emerge. We have examined vaccine safety on male reproductive health. We set up a multicentre (three infertility centers), retrospective study in order to assess semen parameters and fertilization rate of one hundred-six men in a pairwise comparison between the first and second assisted reproduction technology (ART) attempt, performed respectively before and after COVID-19 vaccination. Median time (range) between the first vaccine dose and the second ART cycle was 75 days (39–112). Semen parameters did not change before and after the exposure. Fertilization rate was also similar before and after vaccination. Twenty-five patients (24%) were oligozoospermic before the vaccination while 26 (25%) after the exposure (P = 0.87). Severe asthenozoospermia were present in 11 patients before as well as after the exposure. No difference was observed even after considering different types of vaccines (mRNA or viral vector). COVID-19 vaccination did not affect sperm quality and fertilization capacity of men undergoing ART treatments and should be considered safe for men's reproductive health.

SARS-CoV-2, responsible for the current COVID-19 pandemic that claimed over 5.0 million lives, belongs to a class of enveloped viruses that undergo quick evolutionary adjustments under selection pressure. Numerous variants have emerged in SARS-CoV-2, posing a serious challenge to the global vaccination effort and COVID-19 management. The evolutionary dynamics of this virus are only beginning to be explored. In this work, we have analysed 1.79 million spike glycoprotein sequences of SARS-CoV-2 and found that the virus is fine-tuning the spike with numerous amino acid insertions and deletions (indels). Indels seem to have a selective advantage as the proportions of sequences with indels steadily increased over time, currently at over 89%, with similar trends across countries/variants. There were as many as 420 unique indel positions and 447 unique combinations of indels. Despite their high frequency, indels resulted in only minimal alteration of N-glycosylation sites, including both gain and loss. As indels and point mutations are positively correlated and sequences with indels have significantly more point mutations, they have implications in the evolutionary dynamics of the SARS-CoV-2 spike glycoprotein.

Background ApoAI (apolipoproteins AI) and apoAII (apolipoprotein AII) are structural and functional proteins of high‐density lipoproteins (HDL) which undergo post‐translational modifications at specific residues, creating distinct proteoforms. While specific post‐translational modifications have been reported to alter apolipoprotein function, the full spectrum of apoAI and apoAII proteoforms and their associations with cardiometabolic phenotype remains unknown. Herein, we comprehensively characterize apoAI and apoAII proteoforms detectable in serum and their post‐translational modifications and quantify their associations with cardiometabolic health indices. Methods and Results Using top‐down proteomics (mass‐spectrometric analysis of intact proteins), we analyzed paired serum samples from 150 CARDIA (Coronary Artery Risk Development in Young Adults) study participants from year 20 and 25 exams. Measuring 15 apoAI and 9 apoAII proteoforms, 6 of which carried novel post‐translational modifications, we quantified associations between percent proteoform abundance and key cardiometabolic indices. Canonical (unmodified) apoAI had inverse associations with HDL cholesterol and HDL‐cholesterol efflux, and positive associations with obesity indices (body mass index, waist circumference), and triglycerides, whereas glycated apoAI showed positive associations with serum glucose and diabetes mellitus. Fatty‐acid‒modified ApoAI proteoforms had positive associations with HDL cholesterol and efflux, and inverse associations with obesity indices and triglycerides. Truncated and dimerized proteoforms of apoAII were associated with HDL cholesterol (positively) and obesity indices (inversely). Several proteoforms had no significant associations with phenotype. Conclusions Associations between apoAI and AII and cardiometabolic indices are proteoform‐specific. These results provide “proof‐of‐concept” that precise chemical characterization of human apolipoproteins will yield improved insights into the complex pathways through which proteins signify and mediate health and disease.