Recent advances in pulse protein conjugation and complexation with polyphenols: an emerging approach to improve protein functionality and health benefits.

Pulses have attracted much attention in the food industry due to their low cost, high yield, and high protein content, which promises to be excellent alternative protein sources. Recently, techniques for covalent and noncovalent binding of pulse proteins to polyphenols are expected to solve the problem of their poor protein functional properties. Additionally, these conjugates and complexes also show several health benefits. This review summarizes the formation of conjugates and complexes between pulse proteins and polyphenols through covalent and noncovalent binding and the impact of this structural change on protein functionalities and potential health benefits. Recent studies show that pulse protein functionalities can be influenced by polyphenol dose. This is mainly the case for adverse effects on solubility and enhancement in emulsifying capacity. Also, the conjugates/complexes exhibit antioxidant activity and can alter protein digestibility. The antioxidant activity of polyphenols could be retained after binding to proteins, while the effect on digestibility depends on the type or dosage of polyphenols. Considering the link between polyphenols and their potential health benefits, pulse polyphenols would be a good choice for producing the conjugates/complexes due to their low cost and proven potential benefits. Further studies on the structure-function-health benefits relationship of pulse protein-polyphenol conjugates and complexes are still required, as well as the validation of their application as functional foods in the food industry.

Multivariate analysis for organic milk authentication.

To differentiate organic milk (OM) from conventional milk (CM), an orthogonal projection to latent structure-discriminant analysis (OPLS-DA) model was constructed using δ13C, δ15N, δ18O, 51 elements and 35 fatty acids (FAs) as the variables. So far, most reported studies barely use three or more types of variables, but more variables could avoid one-sidedness and get stabler models. Our multivariate model combines geographical and nutritional parameters and displays better explanatory and predictive abilities (R2X = 0.647, R2Y = 0.962 and Q2 = 0.821) than models based on fewer variables for differentiating OM and CM. In particular, δ15N, Se, δ13C, Eu, K and α-Linolenic acid (ALA) are found to be critical parameters for the discrimination of OM. These results show that the multivariate model based on stable isotopes, elements and FAs can be used to identify OM, and can potentially expand the global databases for quality and authenticity of milk.

Correction: Determining the geographical origin of milk by multivariate analysis based on stable isotope ratios, elements and fatty acids.

Correction for 'Determining the geographical origin of milk by multivariate analysis based on stable isotope ratios, elements and fatty acids' by Siyan Xu et al., Anal. Methods, 2021, DOI: .

Determining the geographical origin of milk by multivariate analysis based on stable isotope ratios, elements and fatty acids.

To construct a reliable discrimination model for determining milk geographical origin, stable isotope ratios including δ13C, δ15N and δ18O, 51 elements and 35 fatty acids (FAs) in milk samples from Australia, New Zealand and Austria were detected and analyzed. It is found that all of the stable isotope ratios in the milk samples of Australia are the highest, followed by those of the samples from New Zealand and Austria. In addition, 14 elements and 8 FAs show different contents in the samples of different countries at the significance level of P < 0.05. Based on these results, a multivariate model with good robustness and predictive ability for authenticating milk origin (R2X = 0.693, Q2 = 0.854) was successfully constructed. Element contents and stable isotope ratios are more reliable variables for milk origin discrimination and Rb, δ18O, Tl, Ba, Mo, Sr, δ15N, Cs, As, Eu, C20:4n6, Sc, C13:0, K, Ca and C16:1n7 are the critical markers in the multivariate model for verifying milk origin.

Amyloid precursor protein binds with TNFRSF21 to induce neural inflammation in Alzheimer's Disease.

OBJECTS: Several evidences suggested that TNFRSF21 exert crucial functions in regulating neuroinflammatory effects, which had been detected in Alzheimer's Disease (AD). We performed many experiments aimed to explore the comprehensively biological functions of TNFRSF21 and its underlying mechanism in AD. METHODS: Twelve normal healthy C57BL6 mice were selected, and AD model mice (APP transgenic model Tg2576 and Tau transgenic model JNPL3) were constructed and TNFRSF21 knockdown was performed in vitro. Western blotting, Co-immunoprecipitation (Co-IP), ELISA assay, flow cytometry and immunofluorescence were performed to explore the biological functions of APP and its underlying mechanism in AD. RESULTS: The expression of TNFRSF21, APP, NF-κB and MAPK8 was increased in APP transgenic model (Tg2576) and Tau transgenic model (JNPL3). The interaction between TNFRSF21 and APP was analyzed by Co-IP at protein level. Based on the results of ELISA, the levels of inflammatory cytokines TNF-α, IL-5, and IFN-γ in the Tg2576 were higher than that in the JNPL3, but hardly observed in the normal group. The increased APP and inflammatory cytokines in AD model were significantly reduced with TNFRSF21 inhibited. Tg2576 group exhibited higher apoptotic rate of neuron cell and increased number of astrocytes than those of the JNPL3 group. CONCLUSIONS: Our studies revealed that APP could promote and bind with TNFRSF21 to regulate the neural inflammatory effects in AD. Inhibiting TNFRSF21 could reduce APP expression and decrease neuroinflammation, which might become potential target for treating AD.

Electroacupuncture improves neurogenic bladder dysfunction through activation of NGF/TrkA signaling in a rat model.

OBJECTIVE: To observe the effect of electroacupuncture on the morphological change of the bladder tissue and the protein expression levels of NGF, TrkA, p-TrkA, AKT, and p-AKT in the bladder tissue of rats with neurogenic bladder after suprasacral spinal cord injury and to preliminarily explore its partial mechanism of action. METHODS: Eighty female Sprague-Dawley rats were randomly divided into blank group, model group, electroacupuncture group, model/siNGF group, and electroacupuncture/siNGF group according to random number table method with 16 rats in each group. Eighty Neurogenic bladder models after suprasacral spinal cord injury were established by adopting a modified spinal cord transection method. Electroacupuncture intervention was conducted on the 19th day after modeling. The bladder function was detected by bladder weight, urine output, serum BUN, and urine protein. After treatment for 7 consecutive days, the rats were killed and the bladder tissues were removed rapidly for microscopic observation of morphological change after hematoxylin and eosin stain and for determination of the protein expression levels of NGF, TrkA, p-TrkA, AKT, and p-AKT via Western blot analysis. The transcription of NGF was measured by reverse-transcription polymerase chain reaction. RESULTS: After treatment, compared with the blank group, the bladder weight of model and electroacupuncture groups were significantly increased (P < 0.05). Compared with the model group, the bladder weight of the electroacupuncture group was decreased (P > 0.05). Compared with the blank group, the urine output of the model group was increased ( P < 0.05). Compared with the blank group, the urine output of the electroacupuncture group was increased ( P > 0.05). Compared with the blank group, the serum BUN of the model group was increased ( P < 0.05). Compared with the blank group, the serum BUN of the electroacupuncture group was increased ( P > 0.05). Compared with the blank group, the urine protein of the model group was increased ( P < 0.05). Compared with the blank group, the urine protein of the electroacupuncture group was increased ( P > 0.05). The expression of NGF, p-TrkA, and p-AKT in the model and electroacupuncture groups was obviously higher than that in the blank group ( P < 0.05). The expression of NGF, p-TrkA, and p-AKT in the electroacupuncture group was higher than that in the model group. The expression of TrkA and AKT were unchanged in blank, model, and electroacupuncture groups ( P > 0.05). After tail vein injection with siNGF lentivirus, the expression of NGF in the model/siNGF group and electroacupuncture/siNGF group was significantly decreased ( P < 0.05). And the protein level of p-AKT and p-TrkA was significantly lower than that of the model and electroacupuncture groups ( P < 0.05). CONCLUSION: Sacral electroacupuncture therapy can improve the expression of both NGF/TrkA signaling and AKT signaling in the local nerve of the damaged spinal cord, inhibit apoptosis of the damaged spinal cord, protect nerve cells, and promote the recovery of the damaged nerve. At the same time, electroacupuncture can promote the coordination of micturition reflex and improve neurogenic bladder function after the spinal cord injury.