Multi-omics signatures in new-onset diabetes predict metabolic response to dietary inulin: findings from an observational study followed by an interventional trial

AIM

The metabolic performance of the gut microbiota contributes to the onset of type 2 diabetes. However, targeted dietary interventions are limited by the highly variable inter-individual response. We hypothesized (1) that the composition of the complex gut microbiome and metabolome (MIME) differ across metabolic spectra (lean-obese-diabetes); (2) that specific MIME patterns could explain the differential responses to dietary inulin; and (3) that the response can be predicted based on baseline MIME signature and clinical characteristics.

METHOD

Forty-nine patients with newly diagnosed pre/diabetes (DM), 66 metabolically healthy overweight/obese (OB), and 32 healthy lean (LH) volunteers were compared in a cross-sectional case-control study integrating clinical variables, dietary intake, gut microbiome, and fecal/serum metabolomes (16 S rRNA sequencing, metabolomics profiling). Subsequently, 27 DM were recruited for a predictive study: 3 months of dietary inulin (10 g/day) intervention.

RESULTS

MIME composition was different between groups. While the DM and LH groups represented opposite poles of the abundance spectrum, OB was closer to DM. Inulin supplementation was associated with an overall improvement in glycemic indices, though the response was very variable, with a shift in microbiome composition toward a more favorable profile and increased serum butyric and propionic acid concentrations. The improved glycemic outcomes of inulin treatment were dependent on better baseline glycemic status and variables related to the gut microbiota, including the abundance of certain bacterial taxa (i.e., Blautia, Eubacterium halii group, Lachnoclostridium, Ruminiclostridium, Dialister, or Phascolarctobacterium), serum concentrations of branched-chain amino acid derivatives and asparagine, and fecal concentrations of indole and several other volatile organic compounds.

CONCLUSION

We demonstrated that obesity is a stronger determinant of different MIME patterns than impaired glucose metabolism. The large inter-individual variability in the metabolic effects of dietary inulin was explained by differences in baseline glycemic status and MIME signatures. These could be further validated to personalize nutritional interventions in patients with newly diagnosed diabetes.

Recurrent landslides predisposed by fault-induced weathering of flysch in the Western Carpathians

The interrelationship between slope deformation and fault-induced weathering as a predisposing factor for the development of sliding is analysed through several case studies from the Western Carpathians in the Czech Republic. The study area comprises flysch nappes with alternating sandstone and shale of different permeability. These lithological structures are affected by systems of faults. Recurring slope instability is found associated with zones of deep weathering in tectonically weakened areas. Climatic variability of landslide activity can be identified during the Holocene by means of radiocarbon dating and pollen analysis. Areas affected by recurring landsliding suggest gradual and cyclic landslide frequency.

Two new common alleles of erythrocyte adenosine deaminase (ADA) in pigs

New adenosine deaminase variants ADA C and ADA D were found by means of agarose gel electrophoresis in pig erythrocytes. Family data supported the hypothesis that these are controlled by codominant alleles ADAC and ADAD. The ADAC allele was present in Large White (q = 0.076), Landrace (q = 0.037) and their crosses with other breeds. The ADAD allele was present in Duroc (q = 0.067) and its crosses. Allele frequencies for six pig breeds are given.

Serologically defined specificities of the pig main histocompatibility complex (SL-A)

Six antigens detectable by the complement-dependent lymphocytotoxic technique were determined in pigs by six groups of alloimmune sera. It was confirmed that these specificities are controlled by the main histocompatibility region (SL-A). Serological and genetic studies showed that the given specificities (provisionally designated L1 to L6) form at least 6 haplotypes. In addition, family studies confirmed the linkaged between SL-A region and C blood group locus. Maximum lod score values are in recombination fraction omicron = 0.2.

Detection of a new non-MHC alloantigenic system (SLD) in pigs

A new, non-MHC cell membrane leucocyte alloantigen was detected in pigs by the complement dependent lymphocytotoxic technique. The new leucocyte system was designated SLD. Its product antigen SLD-1 was demonstrated to segregate independently of the SLA, SLB, SLC, A and E antigens. Family studies supplied evidence of a dominant inheritance of SLD-1. Since an allelic antigen could not be demonstrated, only two alleles for this locus are reported, namely SLD1 and SLD-. No evidence of linkage was detected between the above mentioned leucocyte alloantigenic systems and SLD. The antigen was detected on enriched suspensions of T and B cells from peripheral blood, but it was not detected on erythrocytes, granulocytes and thrombocytes.

Isoimmune anti-A blood group reagents in pigs

Immunization or reimmunization of A-negative pigs with red blood cells (RBC) from A-positive donors yielded anti-A antibodies reacting in high titres with phenotype A(Ac) RBC and, in some cases, in low dilutions, with phenotype Aw(Ap) RBC also. An attempt to raise the anti-A level by immunization with saliva which contained A substance was likewise successful. Repeated immunization of A-negative recipients with the RBC of A-positive donors (compatible in all other factors), with the aid of adjuvant, is recommended as the best way of obtaining Aw typing reagents.

Recombination between the S and the H blood group loci in pigs

The investigation of A-O blood group phenotypes in selected pig families confirms the existence of an S locus which specifically controls the expression of A and O alloantigens. Forty-five informative litters were scored for linkage between the S gene and the H blood group locus. The recombination frequency in 345 offspring was estimated to be 9.56% (33 cross-overs). Specific difficulties involved in the determination of A-O and H phenotypes and the importance of S and H polymorphisms for the determination of Hal genotypes are discussed.

Polymorphism of the SLB serologically defined (non-MHC) alloantigenic system in pigs

Six new antigenic specificities (designated SLB-2 to SLB-7) detectable with polyclonal reagents in the complement-dependent lymphocytotoxic test were determined in the SLB alloantigenic system of pigs. The SLB specificities (including the previously described SLB-1) are controlled by 13 alleles. An analysis of a further 121 double backcross matings (with 817 offspring) confirmed that the products of SLB alleles segregated independently of the SLA haplotypes (swine MHC). In addition, in 112 families of the same mating type (with 746 progeny) the map distance of the SLB locus and the highly polymorphic L blood group locus was found to be 7.82 centimorgans in the heterogametic sex and 12.57 centimorgans in the homogametic sex.

Absence of detectable linkage between the G and H blood group loci in the pig

Morton's lod score method used for the analysis of data from 168 backcross matings (1094 offspring) did not indicate linkage between the G and H blood group loci of the pig. Linkage closer than 0.413 could be excluded at the 1% significance level.

Non-MHC alloantigenic system in pigs (SLC) detected by leucoagglutination

Two cell membrane leucocyte alloantigens were detected in pigs by simple direct agglutination tests. Family studies showed that the locus controlling these antigens was not identical, or in close linkage, with the SLA major histocompatibility complex, SLB leucocyte locus or with the A, E, and N blood group loci. In the studied population, the locus termed SLC (Swine Leucocyte C locus) has two alleles controlling mutually exclusive antigens SLC-1 and SLC-2. The frequency of SLC1 and SLC2 alleles is 0.10 and 0.90, respectively. The antigens have not been detected on erythrocytes and thrombocytes but are well determined on granulocytes, peritoneal macrophages, mononuclears from different sources (thymus, spleen, bone marrow, lymph nodes) and enriched T and B cells from peripheral blood.

Gene order and recombination rates in the linkage group S-Phi-Hal-H-(Po2)-Pgd in pigs

Families of Czech Landrace (94 litters and 636 offspring) were tested for halothane sensitivity, A-O (S), H, PHI and PGD phenotypes. Informative matings for the estimation of recombination rates between marker loci were selected. The following recombination frequencies were established: S - Phi = 4.8% (2.5%-10.7%); S - H = 6.8% (4.3%-11.7%); Phi - H = 2.6% (0.9%-5.3%); H - Pgd = 4.4% (1.6%-8.0%). Cross-overs were observed also between S - Hal, Hal - H and Hal - Pgd, but were not found between Phi - Hal. On the basis of these results it has been possible to revise the position of the S locus in this linkage group. The most probable gene order would be: S - Phi - Hal (or Hal - Phi) - H - (Po2) - Pgd. A striking difference was found between the number of halothane-sensitive pigs (87) and HalnHaln genotypes determined by haplotyping (123). Segregation rates in 19 backcross matings and experimental matings of the animals proved that this difference is mostly due to incomplete penetrance or low expression of halothane sensitivity.

New blood group factors Es, Et and a new allele Ebdgjmt (E16) in the pig E blood group system

By immunizing a miniature sow a monovalent reagent (later designated anti-Es) was prepared, detecting an alternative antigen to the Ej. Blood group factors Ej and Es thus form the fifth genetically closed E subsystem. Analyses of selected raw sera containing anti-Ej led to the determination of a further Ej subgroup (designated Et) which is antithetical, mutually excluding with the blood factor Er. New blood factor Et is inherited by alleles Edeghjmnt (= E9) and (= E16). The investigation in pig breeds kept in CSFR indicated that allele Edeghjmnt occurs in Black and White Prestice breed (qE9 = 0.076 +/- 0.010) while allele Edeghjmnr (= E14) only in miniature pigs (qE9 = 0.147 +/- 0.011) and in wild pigs. In an élite herd of Swedish Landrace kept in CSFR a new complex allele Ebdgjmt (= E16) was found. Its frequency in the population studied was 0.058 +/- 0.022.

The presence of blood group and lymphocyte antigens on porcine granulocytes

Suspensions of highly viable (less than 95%) granulocytes minimally contaminated by other cell types were isolated from the peripheral blood of pigs by a single centrifugation with low molecular weight dextran and after preferential lysis of erythrocytes by hypotonic shock. A complement-dependent cytotoxic test showed the presence of antigens of the SLA major histocompatibility complex, the SLB leucocyte system and the A and E blood group systems on the granulocytes. Some SLA typing reagents against class I (SD) antigens did not react with granulocytes, however, or yielded dubious reactions. The findings showed that the reactivity of SLA sera resembles the reactivity fo human HLA sera. The results also show that compatibility in the SLA, SLB, A and E systems will have to be taken into account when preparing alloimmune sera for the determination of granulocyte-specific antigens of pigs.

The blood group factor Kf and allele Kae in the pig

By means of alloimmune reagents used in the indirect Coombs test and the dextran test a new factor Kf in the K bloodgroup system of pigs was found, controlled by alleles Kacf, Kacef and Kbf. A new allele Kae was also detected. The K system with 6 alleles, 11 phenotypes and 21 combinations of genotypes remains (from the genetic point of view) an open system.

Immune characterization of the Lewis rats inoculated with K2 sarcoma cell line and newly derived R5-28 malignant cells

Sarcoma is a relatively rare malignant disease with high mortality, bad prognosis and response to conventional therapy. Two possible models of this disease were tested: the K2 rat sarcoma cell line, which was described previously, and the new rat R5-28 cell line derived from a spontaneously growing rat neoplasm with sarcoma morphology. While all rats inoculated with K2 cells developed tumours at 22th-25th day after inoculation (D = 22-25), only 60%-75% of R5-28-inoculated rats were affected by tumours. The frequency and progress of the disease depended on the number of inoculated cells. No metastases were detected in both cases. All affected animals showed large splenomegaly. A possible response of some immune system components to tumours was tested. No tumour-infiltrating lymphocytes were revealed in the tumour tissue. Anti-tumour antibodies were not found in tumour-bearing animal sera. Appropriate changes in peripheral blood lymphocyte subsets were explored. While the relative numbers of both NK cells and Tc were impaired, no changes were noted in numbers of CD4+CD8- T helper cells. Leukocytosis with highly increased numbers of CD11b+ myeloid cells displaying variable expression of CD4 was detected in terminal stages of the disease.

Polymorphism of pig serum alpha-protease inhibitor-3 (PI3) and assignment of the locus to the Pi1, Po1A, Po1B, Pi2, Igh linkage group

Polymorphism of an alpha-protease inhibitor, PI3, in pig serum samples was detected using 2D agarose gel (pH 5.4)--polyacrylamide gel (pH 9.0) electrophoresis. Evidence was obtained that the five variants observed (A, B1, B2, C and D) are under genetic control by codominant alleles (Pi3A, Pi3B1, Pi3B2, Pi3C and Pi3D) at one autosomal locus. Variants A, B1, B2 and C inhibited chymotrypsin; there was no appreciable inhibition of trypsin and papain. Variant D did not inhibit chymotrypsin, and therefore its classification as a PI3 variant was put in question. PI3 typing was not possible in about 50% of the studied pigs since in those cases the PI3 variants were either too weak or absent. On the basis of backcross matings and haplotyping in complete families for protease inhibitor loci Pi1, Po1A, Pi2 and Pi3 it was proved that the Pi3 locus belongs to the protease inhibitor gene cluster, and the position of the locus in the linkage group was proposed as being Pi1-Po1A-(Po1B)-Pi3-Pi2-(Igh1, Igh2, Igh3, Igh4).

[Use of the tourniquet in gastrointestinal surgery]

Experimentally induced total or partial intestinal obstructions (ileus) in pigs were surgically treated by means of a tourniquet technique. A lace used in obstetrics for ligation of umbilicus served as the tourniquet. The lace was protracted around an intestine, both ends were threaded through 7-10 cm long rubber tube and fixed by Pean's forceps. During application of the tourniquet we performed suction of the ileus content, devitalization or resection of the affected intestinal segments and intestinal anastomoses. Since the tourniquet provides a flexible compression of intestine with minimum mechanical damage, manipulation without danger of instrument release, and it has negligible cost, this tool gives supposition for the possible use in human surgical praxis.

Changes of clinical biochemical values after bilateral nephrectomy and allotransplantation of the kidney in pigs

In a series of 10 healthy pigs, the normal ranges of the following biochemical parameters in blood serum were assessed: creatinine, urea, mineralogram (Na, K, Cl), uric acid, bilirubin, total protein, cholesterol, blood lipid level, thymol turbidity reaction and activities of alkaline phosphatase, alpha-amylase and transaminases. The changes of these values were followed up in two pigs after bilateral nephrectomy and in 18 pigs subjected to orthotopic allotransplantation of the kidneys. The examination confirmed that creatinine and urea are the most important values with a prognostic impact. However, other biochemical values signalize also renal dysfunction. In the mineralogram, values of Na and K ions are important indicators. Deterioration of renal functions was associated as a rule with a decline of alpha-amylase and alkaline phosphatase. The other examinations did not display any marked changes during renal damage.

Morphology of regressive changes in the kidney following experimental ischaemia

Total or partial renal ischaemia was studied in rats and pigs in a series of experiments, after total devascularization (ligature of renal vessels and ureter); ligature of isolated renal artery; experimental embolization of renal artery by non-resorbable material; devascularization of a specific renal segment by deep, strangulating sutures. Morphological studies showed that the resulting necrotization is represented most frequently by coagulation necrosis, less frequently by colliquating necrosis. Occlusion of the renal artery by embolization or ligature leads only to partial necrotization or atrophy. Total devascularization of the renal hilus or total devascularization of a specific renal segment by strangulating sutures leads to total destruction of the devascularized (devitalized) tissues. Within 8-12 weeks, the whole organ changes into a small residue of connective tissue. The possibility of the use of the devascularization technique in the treatment of tumours is discussed.

Localization of the Po2 locus in the S, Phi, Hal, H, Po2, Pgd linkage group in pigs

The localization of the Po2 locus controlling a polymorphic serum postalbumin was studied in 41 families of the Czech Landrace breed. The haplotypes involving six closely linked loci (S, Phi, Hal, H, Po2, Pgd) were determined for each family member. The crossovers observed between the H, Po2 and Pgd loci indicated that Po2 is located between H and Pgd. The Po2 locus appears to be closer to H [theta = 0.54% (0.06%-1.92%)] than to Pgd [theta = 4.02% (1.67%-7.96%)]. A strong Ha-Po2S association (r = 0.96, P less than 0.001) and H-PO2 linkage disequilibrium (D = 0.2218, P less than 0.01, D/DMax = 0.98) were found.

Development of a semi-inbred line of Landrace pigs. I. Breeding performance and immunogenetic characteristics

During 15 years of inbreeding of pigs (Canadian Landrace) a semi-inbred line has been developed. The inbreeding coefficient (FX) is 0.84, which theoretically corresponds to between 8-9 generations of brother/sister matings. At the highest inbreeding level (0.84) the mean number of newborn piglets in the litter was 7.2 (5 litters, n = 36) including 5 stillborn (13.8%). The mean birth weight of the litter was 8.56 kg (5 litters, n = 31) the mean piglet birth weight was 1.23 kg and at the age of 21 days the mean weight of a litter was 33.24 kg with a mean piglet weight of 5.44 kg. During inbreeding, immunogenetic alloantigenic systems were investigated. Of 15 known erythrocyte systems, alleles of loci J, K, and of the most polymorphic system E, segregated. As to other immunogenetic systems (histocompatibility, leucocyte and allotypes) 2 SLA haplotypes (major histocompatibility complex) and 2 alleles of the SLC leucocyte system segregated. Allotransplants of the skin in SLA compatible siblings survived for a mean of 50.7 days (n = 77) compared with 10.8 days (n = 29) in non-inbred siblings. Tests of blastic transformation activated by T and B lymphocyte mitogens revealed a normal cell-mediated immune response. After immunization with some cell membrane alloantigens a normal humoral response was also recorded. All tested animals were halothane-resistant and tolerated a 10-min exposure to 5% without developing malignant hyperthermia. Depression due to inbreeding was manifested by a reduced reproductive ability (smaller number of piglets, frequent incidence of gonadal hypoplasia, diminution or loss of libido).

[Intestinal invagination in pigs]

The invaginations of small intestine are being described which represent one of possible causes of intestinal ileus. In connection with multiple invaginations, a case of two intussusceptions is being mentioned, in which the peaks of invaginates are directed towards each other. At the same time four theoretically possible double invaginations are presented as well as a proposal for their distinction and indication.

The technique of ureterocystoneostomy in experimental renal orthotopic allotransplantation in the pig

Experimental orthotopic renal allotransplantation performed in pigs allowed us to verify some techniques of ureterocystoneostomies from the urological point of view. For the reconstruction of the urinary pathways we employed anastomosis in 7 cases, and implantation of the ureter into the bladder in 3 cases, using the antireflux technique in 9 animals and the now common ureteral implantation with the terminal segment of the ureter placed in tunnel serosa in 24 animals. The results of our modification confirm the importance of peritoneal plasty of the terminal ureteral segment for the prevention of urinary fistulas. This technique seems to be applicable to reconstruction of urinary pathways in humans.

Effect of antibodies to boar spermatozoa on fertility in sows and rabbits

Immunization of sows with boar spermatozoa had no effect on the sows' fertility or on the number of liveborn young from the first pregnancy. An effect was not recorded until the second pregnancy, when the number of stillborn young increased. The total number of young in the litters was not reduced. Pig and rabbit antibodies to boar spermatozoa had no negative effect on the fertilizing capacity of rabbit spermatozoa. The intravenous administration of antibodies against boar spermatozoa to inseminated female rabbits did not affect their fertility. If the antibodies were injected intramuscularly 7 days before and 10 days after insemination, degenerating fetuses were found in the uterus of inseminated female rabbits. After immunizing sows with boar spermatozoa, specific cellular immune reaction was not demonstrated.

SLB, a new alloantigenic system of the pig

An alloantigen segregating in the double back-cross families, distinct from serologically determinalble transplantation antigens controlled by the major histocompatibility complex (SLA), was detected in pigs by the complement-dependent lymphocytotoxic technique. The system was designated SLB and its product (antigen SLB-A1) was demonstrated in all lymphocytes from the lymph nodes, thymus and peripheral blood, but not in the erythrocytes. Back-cross matings supplied evidence of the dominant heredity of SLB-A1. Detection of further SLB antigens was unsuccessful, so that only two alleles (SLB-A1 and SLB-A-) could be determined in families. Double back-cross families revealed a close linkage between the SLB locus and the L blood group locus. Maximun lod score values were calculated in recombination fraction theta=theta.10.

Linkage of the pig main histocompatibility complex and the J blood group system

Linkage of the main histocompatibility complex (MHC) and the J blood locus was demonstrated in pgis by means of segregation data in families of double back-cross matings. A recombination frequency of 9.82% was estimated. No evidence of close association with the blood group systems A, B, D, E, F, G, H, I, K, L, M, N and O was found.