Paula A. Oliveira’s research while affiliated with University of Trás-os-Montes and Alto Douro and other places

Vermicomposting aims to convert organic residues into valuable end products within a circular economy-based framework. Vineyards generate significant amounts of by-products, namely vine prunings (VPs), typically landfilled or incinerated, and rotten grape clusters (RGCs), which stay on the vines until removed by pruning. This pilot-scale study aimed to explore the role of two earthworm species (Eisenia fetida and Eisenia andrei) in transforming VP and RGC substrates by evaluating their physicochemical properties, phytotoxicity, and polyphenolic content before and after vermicomposting and the microbial activity at the end of the process. The substrates were vermicomposted in 2 L containers with coconut fiber (1:1 ratio) and 7.5 g of each earthworm species (clitellated and non-clitellated) per container for 100 days, with the earthworm biomass monitored every other week. Phytotoxicity was assessed using garden cress (Lepidium sativum L.) and lettuce (Lactuca sativa L.) seeds, and biological stability was assessed by microbial activity and polyphenolic content evaluation using the Folin–Ciocalteu method. The results showed that differences in the vermicompost properties were primarily substrate-dependent. The RGC-based vermicomposts exhibited higher electrical conductivity and P, K, S, and B levels, while the VP-based composts had higher C/N ratios. E. fetida produced vermicomposts with significantly higher K, Ca, and Mg contents and consistently lower phytotoxicity in germination assays with garden cress and lettuce, compared with E. andrei. Vermicomposting led to a decrease in polyphenolic content for both species. This study highlights the importance of earthworm species selection for vermicomposting vineyard residues. Further research should explore how these species perform with other residues to understand their suitability for producing high quality vermicomposts.

Background/Aim Human papillomavirus (HPV) is the most common sexually transmitted infectious agent and, in cases of persistent infection, may cause cancer. This study evaluated the toxicological and antitumor properties of Mentha spicata extract (MSE) in KP14HPV16 mice, which carry HPV16 oncogenes. Materials and Methods Thirty-three female FVB/n mice (Mus musculus), including 17 HPV-transgenic and 16 wild-type (WT) mice, were divided into six groups. The control groups received tap water (WT-C, n=5, and HPV-C, n=6), while the treatment groups received either 0.50 mg/ml MSE (WT-50 and HPV-50, n=6) or 0.55 mg/ml MSE (WT-55 and HPV-55, n=5) in drinking water for 28 days. Afterwards, animals were sacrificed, and blood and organs were collected for histopathological and biochemical analysis. Results The main phenolic compounds in MSE were rosmarinic acid and luteolin-O-glucoronide. MSE did not significantly affect weight gain in WT mice; however, WT-55 gained significantly more weight than HPV-55. MSE demonstrated antioxidant activity as indicated by the modulation of hepatic superoxide dismutase and glutathione S-transferase (GST) activity, as well as renal GST activity, in MSE-treated HPV groups. MSE did not reduce histological lesion incidence or systemic inflammation in HPV16-transgenic mice. Conclusion In general, while MSE was safe and exhibited antioxidant activity, it did not significantly impact HPV16-induced lesions, warranting further research to assess systemic effects with different concentrations and durations.

Cancer-associated cachexia (CAC), also known as wasting syndrome, is a systemic condition that affects multiple tissues and organs via a variety of metabolic pathways. Systemic inflammation, progressive weight loss, depletion of adipose tissue, and skeletal muscle impairment are some of the hallmark features of cachexia. Despite various studies on the clinical features of CAC, the complexity of the syndrome continues to pose significant challenges in clinical practice, leading to late diagnoses and the absence of a standardised treatment. Men and women respond differently to CAC, which may be prompted by the pre-existing physiologic sex differences. This review presents the sexual dimorphism associated with the hallmark pathways involved in CAC. A comprehensive understanding of sexual dimorphism in these pathways could drive research on cachexia to prioritise the inclusion of more females in related studies in order to achieve personalised sex-based therapeutic approaches and, consequently, enhance treatment efficacy and better patient outcomes.

Breast cancer remains a significant global health issue, affecting both humans and companion animals, particularly female dogs and cats, where mammary tumors are among the most common cancers. Strategies to minimize the impact of this disease on patients, pet owners, and veterinary medicine are essential. This study analyses the effects of resistance training on the development of chemically induced mammary cancer in female Wistar rats, divided into four groups: sedentary control (CTR), sedentary induced (CTR+N-methyl-N-nitrosourea (MNU)), exercised control (EX), and exercised induced (EX+MNU). The exercise protocol involved ladder climbing three times a week for 18 weeks with the load progressively increasing. At the study’s end, blood and histopathological samples were collected and analyzed. Although tumor onset occurred two weeks earlier and incidence was slightly higher in the exercised group (EX+MNU) compared to the control group (CTR+MNU), the mortality rate was lower, and the malignancy was not as aggressive. No systemic inflammation was observed, as the levels of albumin, C-reactive protein (CRP), and interleukin 6 (IL-6) in the MNU groups remained similar to the controls. Exercise has been shown to promote overall health by increasing physical fitness, boosting immunological function, and improving metabolic health. These findings may offer valuable insights into the potential role of resistance training in managing mammary cancer in companion animals. However, further research is required to assess clinical applicability and to establish safe and effective exercise protocols for veterinary oncology.

Recent advancements in molecular biology have led to the discovery of potential biomarkers for the diagnosis of acute kidney disease (AKD) and chronic kidney disease (CKD). The use of multiple biomarkers in the diagnosis of kidney disease has the potential to enhance both specificity and sensitivity, enabling early detection and intervention that could ultimately reduce morbidity and mortality rates. This review provides an overview of studies on urine and blood biomarkers and examines their utility and significance in various clinical settings. Further and continuous research is needed to support the application of these biomarkers in clinical practice to facilitate early diagnosis, guidance for different interventions, and the monitoring of disease progression.

Introduction: Bladder cancer presents a significant health problem worldwide, with environmental and genetic factors contributing to its incidence. Histologically, it can be classified as carcinoma in situ, non-muscle invasive and muscle-invasive carcinoma, each one with distinct genetic alterations impacting prognosis and response to therapy. While traditional transurethral resection is commonly performed in carcinoma in situ and non-muscle invasive carcinoma, it often fails to prevent recurrence or progression to more aggressive phenotypes, leading to the frequent need for additional treatment such as intravesical chemotherapy or immunotherapy. Despite the advances made in recent years, treatment options for bladder cancer are still lacking due to the complex nature of this disease. So, animal models may hold potential for addressing these limitations, because they not only allow the study of disease progression but also the evaluation of therapies and the investigation of drug repositioning. Areas covered: This review discusses the use of animal models over the past decade, highlighting key discoveries and discussing advantages and disadvantages for new drug discovery. Expert opinion: Over the past decade animal models have been employed to evaluate new mechanisms underlying the responses to standard therapies, aiming to optimize bladder cancer treatment. The authors propose that molecular engineering techniques and AI may hold promise for the future development of more precise and effective targeted therapies in bladder cancer.

This study aimed to investigate the impact of a Western diet and resistance training on cardiac remodeling in a rat model of chemically induced mammary cancer. Fifty-six female Wistar rats were randomly assigned to one of eight experimental groups, evaluating the impact of Western and standard diets, exercise and sedentarism, and the induction of mammary cancer. Mammary cancer was induced via the intraperitoneal administration of N-methyl-N-nitrosourea (MNU) (50 mg/kg) at seven weeks of age. The resistance training protocol consisted of ladder climbing three times per week for an 18-week period, with a gradual increase in load over time. At the end of the 20-week experimental period, the animals were anesthetized and underwent echocardiography. Subsequently, the animals were euthanized, and organs and visceral adipose tissue (VAT) were collected and analyzed. A histopathological examination was performed on the mammary tumors. The Western diet increased relative VAT and contributed to cardiovascular and tumor-related changes, including an increase in interventricular septum thickness (IVS) and left ventricle posterior wall thickness (LVPW) at end-systole. Exercise reduced fat accumulation, improved cardiac performance, and helped regulate cardiovascular function, as indicated by a higher eccentricity index (EI) in the WD+EX group compared to the WD group. The WD was associated with increased VAT accumulation and initially delayed tumor initiation; however, over time, it contributed to bigger tumor aggressiveness. This diet also delayed tumor initiation but increased LVPW. Exercise, when combined with a WD, accelerated tumorigenesis, malignant transformation and invasiveness, resulted in the higher prevalence of invasive tumors. These findings underscore the complex and potentially compounding effects of diet and exercise on cancer progression.

Sarcopenia and cancer cachexia are two life-threatening conditions often misdiagnosed. The skeletal muscle is one of the organs most adversely affected by these conditions, culminating in poor quality of life and premature mortality. In addition, it has been suggested that chemotherapeutic agents exacerbate cancer cachexia, as is the case of doxorubicin. Herein, we sought to investigate markers of inflammation and neuromuscular junction (NMJ) remodeling during aging and in response to cancer or cancer with chemotherapy. To address this, we utilized female rats across three age groups – young, adult, and old – to examine age-related changes, with old rats serving as a sarcopenia model. Additionally, a chemically-induced breast cancer (BCa) model was implemented in female adult rats, both without (adult BCa) or with doxorubicin administration (adult BCaDOX), to study cancer cachexia. The atrophy of the gastrocnemius muscle was observed in old, adult BCa and adult BCaDOX rats compared to adult ones. No signs of inflammation or NMJ impairment were observed in adult BCa or adult BCaDOX rats, except for the low levels of the subunit α1 of the acetylcholine receptor in adult BCaDOX rats compared to adult ones. In contrast, old rats presented high serum levels of interleukin 6, brain-derived neurotrophic factor (BDNF) and calcitonin gene-related peptide compared to young rats. In the gastrocnemius muscle, BDNF levels were decreased in old rats compared to adult rats, suggesting impaired skeletal muscle regeneration upon age-induced damage. The BDNF muscle levels were inversely correlated with its levels in circulation in adult and old rats. Hence, this work highlights BDNF as a specific biomarker of age-induced skeletal muscle atrophy, at least, in the differential diagnosis against cancer- or cancer with chemotherapy-induced muscle wasting.