Conjugated linoleic acid metabolite impact in colorectal cancer: a potential microbiome-based precision nutrition approach.

Colorectal cancer (CRC) is the second most deadly and the third most diagnosed cancer in both sexes worldwide. CRC pathogenesis is associated with risk factors such as genetics, alcohol, smoking, sedentariness, obesity, unbalanced diets, and gut microbiota dysbiosis. The gut microbiota is the microbial community living in symbiosis in the intestine, in a dynamic balance vital for health. Increasing evidence underscores the influence of specific gut microbiota bacterial species on CRC incidence and pathogenesis. In this regard, conjugated linoleic acid (CLA) metabolites produced by certain gut microbiota have demonstrated an anticarcinogenic effect in CRC, influencing pathways for inflammation, proliferation, and apoptosis. CLA production occurs naturally in the rumen, and human bioavailability is through the consumption of food derived from ruminants. In recent years, biotechnological attempts to increase CLA bioavailability in humans have been unfruitful. Therefore, the conversion of essential dietary linoleic acid to CLA metabolite by specific intestinal bacteria has become a promising process. This article reviews the evidence regarding CLA and CLA-producing bacteria as therapeutic agents against CRC and investigates the best strategy for increasing the yield and bioavailability of CLA. Given the potential and limitations of the present strategies, a new microbiome-based precision nutrition approach based on endogenous CLA production by human gut bacteria is proposed. A literature search in the PubMed and PubMed Central databases identified 794 papers on human gut bacteria associated with CLA production. Of these, 51 studies exploring association consistency were selected. After excluding 19 papers, due to health concerns or discrepancies between studies, 32 papers were selected for analysis, encompassing data for 38 CLA-producing bacteria, such as Bifidobacterium and Lactobacillus species. The information was analyzed by a bioinformatics food recommendation system patented by our research group, Phymofood (EP22382095). This paper presents a new microbiome-based precision nutrition approach targeting CLA-producing gut bacterial species to maximize the anticarcinogenic effect of CLA in CRC.

Possible relationship between the gut leaky syndrome and musculoskeletal injuries: the important role of gut microbiota as indirect modulator.

This article aims to examine the evidence on the relationship between gut microbiota (GM), leaky gut syndrome and musculoskeletal injuries. Musculoskeletal injuries can significantly impair athletic performance, overall health, and quality of life. Emerging evidence suggests that the state of the gut microbiota and the functional intestinal permeability may contribute to injury recovery. Since 2007, a growing field of research has supported the idea that GM exerts an essential role maintaining intestinal homeostasis and organic and systemic health. Leaky gut syndrome is an acquired condition where the intestinal permeability is impaired, and different bacteria and/or toxins enter in the bloodstream, thereby promoting systemic endotoxemia and chronic low-grade inflammation. This systemic condition could indirectly contribute to increased local musculoskeletal inflammation and chronificate injuries and pain, thereby reducing recovery-time and limiting sport performance. Different strategies, including a healthy diet and the intake of pre/probiotics, may contribute to improving and/or restoring gut health, thereby modulating both systemically as local inflammation and pain. Here, we sought to identify critical factors and potential strategies that could positively improve gut microbiota and intestinal health, and reduce the risk of musculoskeletal injuries and its recovery-time and pain. In conclusion, recent evidences indicate that improving gut health has indirect consequences on the musculoskeletal tissue homeostasis and recovery through the direct modulation of systemic inflammation, the immune response and the nociceptive pain.

Acute Effects of Different Overspeed Loads with Motorized Towing System in Young Athletes: A Pilot Study.

Overspeed is a training method used to improve running speed, although its effects are not supported by consensual scientific evidence. The overspeed stimulus can be boosted by several methods, including motorized towing devices. Our objectives were to analyze the acute effects of three overspeed loads in young athletes and to select optimal loads for training periods. Eight young athletes (16.73 ± 1.69 years) performed one unassisted sprint and three assisted sprints, and kinematic and biomechanical data were compared. Significant increases (p < 0.05) in step velocity and step length were found with 2, 4, and 5.25 kg in maximum running speed, flight time and horizontal distance from the first contact to the vertical projection of the center of mass with 4 and 5.25 kg. Significant time decreases were found in 5 m flying sprint and contact time with 4 and 5.25 kg, and no significant changes were observed in step rate. The individually recommended loads would be between 3.47 ± 0.68% and 6.94 ± 1.35% body weight. Even having limitations, we can understand this work and its results as a pilot study to replicate the methodology and the use of new devices to more broadly investigate the effects of overspeed.

Acute effects of overspeed stimuli with towing system on athletic sprint performance: A systematic review with meta-analysis.

Overspeed-based training is widely used to improve athletes' maximum running speed and towing systems are one of the most frequently employed methods for this purpose. However, the effectiveness of this modality has not been thoroughly determined. This review analyzes the acute effects of overspeed conditions with towing systems in sprinters. The articles were searched, analysed and selected following the PRISMA methodology in the PubMed, SPORTDiscus and Google Scholar databases. Sixteen studies were included, with a total sample of 240 men and 56 women (14 to 31y; 1.73 to 1.82 m; 66.2 to 77.0 kg). The main acute responses found were: 1) an increase in maximum running speed (ES = 1.54, large), stride length (ES = 0.92, moderate), flight time (ES = 0.28, small) and stride rate (ES = 0.12, trivial); and, 2) a decrease in contact time (ES = 0.57, small). However, analysis of the reported ground reaction forces and electromyography data did not provide enough consistent evidence to conclusively determine whether the changes are due to a greater muscular response of the athlete or the effect of the towing system. Future research should focus on studying the mechanisms responsible for the observed acute effects.

The GALNTL6 Gene rs558129 Polymorphism Is Associated With Power Performance.

Díaz, J, Álvarez Herms, J, Castañeda, A, Larruskain, J, Ramírez de la Piscina, X, Borisov, OV, Semenova, EA, Kostryukova, ES, Kulemin, NA, Andryushchenko, ON, Larin, AK, Andryushchenko, LB, Generozov, EV, Ahmetov, II, and Odriozola, A. The GALNTL6 gene rs558129 polymorphism is associated with power performance. J Strength Cond Res 34(11): 3031-3036, 2020-The largest genome-wide association study to date in sports genomics showed that endurance athletes were 1.23 times more likely to possess the C allele of the single nucleotide polymorphism rs558129 of N-acetylgalactosaminyltransferase-like 6 gene (GALNTL6), compared with controls. Nevertheless, no further study has investigated GALNTL6 gene in relation to physical performance. Considering that previous research has shown that the same polymorphism can be associated with both endurance and power phenotypes (ACTN3, ACE, and PPARA), we investigated the association between GALNTL6 rs558129 polymorphism and power performance. According to this objective we conducted 2 global studies regarding 2 different communities of athletes in Spain and Russia. The first study involved 85 Caucasian physically active men from the north of Spain to perform a Wingate anaerobic test (WAnT). In the second study we compared allelic frequencies between 173 Russian power athletes (49 strength and 124 speed-strength athletes), 169 endurance athletes, and 201 controls. We found that physically active men with the T allele of GALNTL6 rs558129 had 5.03-6.97% higher power values compared with those with the CC genotype (p < 0.05). Consistent with these findings, we have shown that the T allele was over-represented in power athletes (37.0%) compared with endurance athletes (29.3%; OR = 1.4, p = 0.032) and controls (28.6%; OR = 1.5, p = 0.015). Furthermore, the highest frequency of the T allele was observed in strength athletes (43.9%; odds ratio [OR] = 1.9, p = 0.0067 compared with endurance athletes; OR = 2.0, p = 0.0036 compared with controls). In conclusion, our data suggest that the GALNTL6 rs558129 T allele can be favorable for anaerobic performance and strength athletes. In addition, we propose a new possible functional role of GALNTL6 rs558129, gut microbiome regarding short-chain fatty acid regulation and their anti-inflammatory and resynthesis functions. Nevertheless, further studies are required to understand the mechanisms involved.

Genetic Variants and Hamstring Injury in Soccer: An Association and Validation Study.

PURPOSE: This study aimed to investigate the association of candidate single nucleotide polymorphisms (SNP) with noncontact hamstring muscle injuries in elite soccer players and to create and validate a model to assess the risk of hamstring injury. METHODS: A total of 107 elite male outfield players were prospectively followed for six seasons. Players were genotyped for 37 SNP previously investigated in relation to musculoskeletal injuries. The association of SNP, previous injury, age, level of play, position, and anthropometric data with 129 hamstring injuries (413 observations) was investigated in the discovery phase (2010-2015), and a multivariable Cox frailty model was created using forward selection. The model's discriminative ability was tested in the validation phase (2015-2016, 31 injuries, 98 observations) using Harrell's C index. RESULTS: Five SNP were found to be significantly associated with hamstring injury in a multivariable model: matrix metalloproteinase 3 rs679620 (A vs G, hazard ratio [HR] = 2.06, 95% confidence interval [CI] = 1.51-2.81), tenascin C rs2104772 (A vs T, HR = 1.65, 95% CI = 1.17-2.32), interleukin 6 rs1800795 (GG vs GC + CC, HR = 1.68, 95% CI = 1.11-2.53), nitric oxide synthase 3 rs1799983 (G vs T, HR = 1.35, 95% CI = 1.01-1.79), and hypoxia-inducible factor-1α rs11549465 (CC vs CT, HR = 2.08, 95% CI = 1.00-4.29). Age also entered the model (≥24 vs <24 yr, HR = 2.10, 95% CI = 1.29-3.42). The model showed acceptable discrimination in the discovery phase (C index = 0.74), but not in the validation phase (C index = 0.52). CONCLUSION: Genetic variants appear to be involved in the etiology of hamstring injuries but were not found to have predictive value by themselves. Further research, increasing the number of genetic variants and including environmental factors in complex multifactorial risk models, is necessary.

I-DNASE21 system: development and SWGDAM validation of a new STR 21-plex reaction.

I-DNASE21 is a new STR multiplex system that amplifies 21 STR autosomal loci, plus the amelogenin locus in one reaction. This system has been designed to analyze all the STR loci included in the Combined DNA Index System (CODIS), Interpol Standard Set of Loci (ISSL), Extended European Standard Set (ESS-Extended), UK National Criminal Intelligence DNA Database (NDNAD) and German Core loci (GCL). This manuscript presents the validation of the I-DNASE21 system according to the revised guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM). The results of this validation, added to the extremely high discriminatory power showed, suggest that I-DNASE21 could be a potentially helpful tool for identification and kinship determination even in complex paternity cases.

Development and validation of a multiplex reaction analyzing eight miniSTRs of the X chromosome for identity and kinship testing with degraded DNA.

We report the development of an effective system for analyzing X chromosome-linked mini short tandem repeat loci with reduced-size amplicons (less than 220 bp), useful for analyzing highly degraded DNA samples. To generate smaller amplicons, we redesigned primers for eight X-linked microsatellites (DXS7132, DXS10079, DXS10074, DXS10075, DXS6801, DXS6809, DXS6789, and DXS6799) and established efficient conditions for a multiplex PCR system (miniX). The validation tests confirmed that it has good sensitivity, requiring as little as 20 pg of DNA, and performs well with DNA from paraffin-embedded tissues, thus showing potential for improved analysis and identification of highly degraded and/or very limited DNA samples. Consequently, this system may help to solve complex forensic cases, particularly when autosomal markers convey insufficient information.

miRNA analysis in vitreous humor to determine the time of death: a proof-of-concept pilot study.

We hypothesized that miRNAs present in vitreous humor could be a sort of "biological black box," storing information about physiological and environmental circumstances at death. As a proof of concept, we analyzed the vitreous humor miRNA signature to explore its forensic potential applications, such as determining the time of the day at death. The miRNAs present in vitreous humor from individuals who died at daytime or at nighttime were analyzed by quantitative real-time polymerase chain reaction (qPCR) array. Target miRNAs showing significant differences between groups were studied in a larger sample by individual qPCR assays. After array analysis of miRNAs in seven samples, significant expression differences were detected between individuals who died at daytime and at nighttime regarding mir-34c, mir-541, mir-888, mir-484, and mir-142-5p. miR-222 appeared as the best reference gene. The results were replicated in 34 vitreous humor samples, and the day-night differences were confirmed for miR-142-5p and miR-541, suggesting that miRNA levels may be related to either the ambient light or the circadian clock at the time of death. There was no correlation between miRNA levels and the time elapsed after death, suggesting that they were stable at least for 24 h. In conclusion, this report supports the potential forensic utility of the analysis of miRNAs in the vitreous humor in applications such as determining the time of death.

Chimerism analysis in transplant patients: a hypothesis-free approach in the absence of reference genotypes.

INTRODUCTION: During routine analysis of chimerism in bone marrow transplant patients pre-transplant genotype of the recipient or the donor might lack. We aimed to develop a new method to analyze DNA results suitable when reference genotypes are not available. METHODS: The method was based on the balance between heterozygotes. It was implemented in a standard computer spreadsheet, and considered the hypothetical donor-recipient genotype combinations. Hypotheses with peak height ratios and allele sharing tendency above a critical threshold were accepted. The results were compared with those obtained with prior knowledge of reference genotypes. RESULTS: The algorithm predicted correctly the proportion of donor/recipient chimerism, even in the absence of reference genotypes. In fact, the predicted values were closely correlated (r(2)>0.98) and free of systematic bias (slope 0.98-1.04), in comparison with the reference values obtained with prior knowledge of the donor and recipient genetic profiles. CONCLUSIONS: This study constitutes a proof-of-concept of the application of the heterozygote balance for the quantitative study of chimerism. The algorithm computes post-transplant chimerism in an easy and time-efficient way, even when the donor and recipient reference genotypes are unavailable. Therefore, it can be a useful tool for laboratories involved in chimerism analysis.

Mitochondrial DNA control region variation in an autochthonous Basque population sample from the Basque Country.

Mitochondrial control region (16024-576) sequences were generated from 106 samples from autochthonous Basques from the Autonomous Community of the Basque Country. It is especially important to generate mtDNA databases from isolated populations in order to maximize the power of discrimination of this molecular marker. It also represents a useful approach to carry out a more accurate haplogroup classification. This is the first database report of complete control region sequences in an autochthonous Basque population sample. Strict selection criteria of autochthonous individuals, automation of laboratory processing and independent reviews of the raw electropherograms ensure the high quality of these sequences and their utility as reference population data of the autochthonous Basque population.

Y-STR variation in the Basque diaspora in the Western USA: evolutionary and forensic perspectives.

Individuals of Basque origin migrated in large numbers to the Western USA in the second half of the nineteenth century, and the flow continued with less intensity during the last century. The European source population, that of the Basque Country, has long been a cultural and geographical isolate. Previous studies have demonstrated that Y-STR frequencies of Basques are different from those of other Spanish and European populations [1]. The Basque diaspora in the Western USA is a recent migration, but the founder effect and the incorporation of new American Y chromosomes into the paternal genetic pool of the Basque diaspora could have influenced its genetic structure and could thus have practical implications for forensic genetics. To check for genetic substructure among the European source and Basque diaspora populations and determine the most suitable population database for the Basque diaspora in the Western USA, we have analysed the haplotype distribution of 17 Y-STRs in both populations. We have found that the Basque diaspora in the Western USA largely conserve the Y chromosome lineage characteristic of the autochthonous European Basque population with no statistically significant differences. This implies that a common 17 Y-STR Basque population database could be used to calculate identification or kinship parameters regardless of whether the Basque individuals are from the European Basque Country or from the Basque diaspora in the Western USA.

Development and validation for identity testing of I-DNADuo, a combination of I-DNA1 and a new multiplex system, I-DNA2.

The I-DNADuo multiplex system combination is composed of previously validated I-DNA1 and a new short tandem repeat (STR) multiplex named I-DNA2 that analyses 11 STR loci plus amelogenin. I-DNADuo, with amplicon sizes ranging from 57 to 298 bp, is specifically designed to analyse amelogenin and 15 STR loci (ten of them plus amelogenin in duplicate), including all the STR loci of the CODIS, ISSL and ECL databases, and seven of the eight in GCL. The validation of I-DNADuo shows that it is a highly sensitive, robust multiplex system for obtaining individual genetic profiles and for detecting and preventing allelic dropouts.

The maternal legacy of Basques in northern navarre: New insights into the mitochondrial DNA diversity of the Franco-Cantabrian area.

Autochthonous Basques are thought to be a trace from the human population contraction that occurred during the Last Glacial Maximum, based mainly on the salient frequencies and coalescence ages registered for haplogroups V, H1, and H3 of mitochondrial DNA in current Basque populations. However, variability of the maternal lineages still remains relatively unexplored in an important fraction of the Iberian Basque community. In this study, mitochondrial DNA diversity in Navarre (North Spain) was addressed for the first time. To that end, HVS-I and HVS-II sequences from 110 individuals were examined to identify the most relevant lineages, including analysis of coding region SNPs for the refinement of haplogroup assignment. We found a prominent frequency of subhaplogroup J1c (11.8%) in Navarre, coinciding with previous studies on Basques. Subhaplogroup H2a5, a putative autochthonous Basque lineage, was also observed in Navarre, pointing to a common origin of current Basque geographical groups. In contrast to other Basque subpopulations, comparative analyses at Iberian and European scales revealed a relevant frequency of subhaplogroup H3 (10.9%) and a frequency peak for U5b (15.5%) in Navarre. Furthermore, we observed low frequencies for maternal lineages HV0 and H1 in Navarre relative to other northern Iberian populations. All these findings might be indicative of intense genetic drift episodes generated by population fragmentation in the area of the Franco-Cantabrian refuge until recent times, which could have promoted genetic microdifferentiation between the different Basque subpopulations.

Variability of the entire mitochondrial DNA control region in a human isolate from the Pas Valley (northern Spain).

In this study, we analyzed the entire mtDNA control region in 61 unrelated individuals from the Pas Valley (Cantabria), a human isolate from northern Spain, to evaluate the suitability of this analysis to increase the power of discrimination of this locus for forensic purposes in human isolates. Low values obtained for the diversity parameters confirmed the relative isolation of this human group. The main findings of this study indicated that even the analysis of the entire mtDNA control region may have important limitations for use in forensic casework when dealing with human isolates: none of the 44 individuals who exhibited identical HVI-HVII haplotypes could be further differentiated by analysis of segment HVIII. Nevertheless, analysis of the entire mtDNA control region proved to be useful to determine the ancestry of the samples examined, by contributing to the confirmation, and, on occasion, even to the refinement of the haplogroup assignment.

Quality standards in Biobanking: authentication by genetic profiling of blood spots from donor's original sample.

The field of Biobanking requires extensive work to maintain traceability of samples. However, sometimes the necessity to authenticate a sample may arise. To address these circumstances, we herein present a method for authenticating derivatives by using a blood spot from each donor, attached to a sample authentication form, by means of genetic profiling. Blood spots are collected at the time a blood sample is donated at a health centre and before processing the blood sample at the biobank. To test the validity of our approach over time, we analyzed 26 blood spots stored at room temperature in our facilities for more than 15 years. DNA was successfully extracted from the three storage materials tested in this study and 15 STR markers plus amelogenin were subsequently analyzed. The storage of a small blood spot attached to a sample authentication form proved to be efficient for genetic profiling and, therefore, may constitute a long-lasting (at least 15 years), cost-effective and effortless approach for genetic authentication of samples in biobanks.